Schaeffler introduces new gearbox, bearings and custom linear motion systems for collaborative robots

Today’s advanced automation and production plants need lightweight robots (LWRs) and collaborative robots (cobots) that are highly dynamic and accurate. Drawing on its many years of experience in industrial automation, Schaeffler has developed a variety of solutions for LWRs and cobots, opening up new opportunities in a fast-growing market.

The new conical thrust cage needle roller bearing from Schaeffler is used both as an articulated arm bearing in Light Weight Robots (LWR') and cobots and as the main bearing support for the company’s new RTWH precision gearbox. This combination of gearbox and bearing ensures the most compact design envelope and the greatest rigidity possible.

The double-row conical thrust cage needle roller bearing has more load-bearing rolling elements than the crossed roller bearings currently used for articulated-arm bearing supports, while maintaining the same design envelope. Customers therefore have the option of using smaller-sized bearings, thereby saving on space and weight.

The bearing’s X-arrangement of needle rollers in two raceways offers support distances that, depending on installed size, increases rigidity by at least 30% compared to crossed roller bearings. Furthermore, by housing the rolling elements in cage guides and having them configured in two raceways instead of one, the bearing delivers a 20% reduction in friction.

Schaeffler also offers ready-to-install, silk hat-type speed reducers for use in robot articulated joints. The gearbox combines high gear ratios – and correspondingly high torques – with relatively lightweight construction. The gearbox is characterised by clearance-free operation, high positioning accuracy, compactness and high durability.

Plug-and-play linear axes made-to-order
Schaeffler also offers compact, ready-to-install linear axis solutions for cobots. These consist of a tandem actuator using Schaeffler's 4 row linear ball bearing guidance systems, a corresponding adapter plate for the cobot, an appropriate motor/gearbox unit, prefabricated motor cables, a drag chain for all of the cobot’s supply lines/cables, and a motor controller. The solutions are supplied complete with Profibus, Profinet, and EtherCAT interfaces for connection to the customer’s control system. The linear axis solutions have various options for connecting to the motor/gearbox units.

Depending on customer requirements, the linear axis can be supplied in various lengths and can be driven by a ball screw drive, a toothed belt drive, or a linear motor.

In the tandem actuator, which forms the basis of the linear axis, the guide carriage runs along two parallel 4-row type monorail guidance systems (four-row linear recirculating ball bearing and guideway assemblies). Due to its compact design envelope, the tandem actuator is ideally suited for use in applications involving high carrying and moment loads.

For applications that require extremely high carrying and moment-load capacities, customers have the option of running the guide carriage on a six-row linear recirculating ball bearing and guideway assembly in premium X-life quality.