Image Number 4 for United States Patent #7159677.
A compact and lightweight drive mechanism for an electrically powered vehicle such as a wheelchair or a scooter. The compact drive mechanism includes a gearmotor combining a motor and a gearbox. High strength rare earth magnets and a large diameter enable the motor to generate a high torque. Gearmotor efficiency is maximized by placing the motor and gearbox in a direct drive relationship, with the shafts of both motor and gearbox parallel to one another. The compact drive mechanism weighs less than conventional drive mechanisms and occupies less space. The compact drive mechanism therefore improves efficiency and lowers power requirements over conventional systems.