DC motor and gearhead – but not your standard selection.
Why would you select a spur gearhead over a more popular planetary design for a DC servo system? Answer: back drivability.
More often than not a DC gear motor specified for an application with even modest space constraints will utilise planetary gearboxes. The fact is there are simply more teeth in a smaller space to spread the load.
However, many high ratio planetary gearhead designs have floating stages that when back driven will give irregular feedback torque characteristics. Even in some cases with dynamic inputs the planetary gearmotor can jam. It is in this instance that a spur gearhead can be a better solution. It must be said that not any spur gearhead will work. The automation market is flooded with low cost spur gearhead products that are often of such low quality that they would not be recommended by maxon motor for power transmission in either direction although the unit pictured is an exception. This 45mm spur gearhead features a very robust all metal construction with large output bearings capable of up to 190N radial load and 60N of dynamic axial load. Reduction gearing efficiency of 87% and a hardened stainless steel shaft. The shaft in this instance has been modified with a transverse bore directly alongside a milled flat to suit the customers load affixation method. A 60W 30mm diameter motor is being used which in itself required the machining of specialised adaptor flanges. Custom modifications such as these particularly suit the diverse and changing requirements of the robotic and haptic control fields.
Contact maxon motor engineers to “spur” your robot into motion. +61 2 9476 4777