New short gears from Nabtesco

Classic strain wave gears with a short-build design are 65% shorter than standard designs - offering an ideal solution for compact axes and joints as those used, for example, in exoskeletons, humanoid robots, and cobots. However, the short-build design comes with limitations, as power density and life time are reduced considerably. With its new short gear technology, Nabtesco is pushing existing boundaries and gives rise to hitherto inconceivable possibilities in robotics and automation when it comes to compact dimensions, efficiency, availability, and productivity.

The new short gears deliver 120% in power density and 140% in life time (expanding the market standard of 7,000 hours to 10,000 h) while keeping the same size. The higher rated torque also has a positive effect on the repeatable peak torque, the acceleration torque and the limit torque for emergency stop, ratcheting, buckling, and collision, elevating them by nearly 20%. The higher power density opens up new possibilities for design engineers: smaller sizes and lighter connection designs paired with savings in material and cost. At the same time, the longer service life improves machine availability and reduces downtime.

Ideal solution for limited axial installation lengths

The new short gears play to their strengths where every millimetre of axial installation space counts and high power density is of the essence at the same time. Their core applications include wearables such as exoskeletons as well as compact robot joints for humanoid robots and cobots, especially in the end axes. Other key areas of applications include such medical engineering systems as operating robots, dental milling machines and detector/optical adjustment mechanisms in imaging systems. Even industrial robots, positioning and turning axes, machine tools, and watch production benefit from compact strain wave gears.

Hollow shaft gears for torques ranging from 4.5 to 115 Nm

Nabtesco's short gears cover a torque spectrum of 4.5 to 115 Nm and can be realised as hat-type gears (HTG) and cup-type gears (CTG). They have a hollow shaft and offer sufficient space for routing supply lines, cables and hoses through the inside of the gear. This allows for feeding media in a space-saving manner. All strain wave gears can also be customised for the particular application in terms of performance, geometry, material, and interfaces, including functional, component and system integration, as required.