The gear ratio is a fundamental specification. It represents the ratio of the rotational speed of the input shaft to the output shaft. For example, a gear ratio of 3:1 means that for every three rotations of the input shaft, the output shaft makes one rotation. Gear ratios for mobile planetary gearboxes can range from relatively low values like 2:1 for applications requiring high - speed output to much higher values such as 10:1 or more for applications demanding high torque multiplication.
The gear ratio is determined by the number and size of the gears in the planetary gear set. A typical planetary gear set consists of a sun gear (connected to the input), planet gears (mounted on a carrier), and a ring gear (which can be fixed or act as the output, depending on the configuration).
Torque Capacity
The torque capacity is specified in Newton - meters (N·m). It indicates the maximum amount of torque that the gearbox can transmit without failure. In mobile applications, torque requirements vary widely depending on the vehicle or machinery type. For example, a small electric vehicle gearbox might have a torque capacity of around 100 - 200 N·m, while a heavy - duty construction vehicle gearbox could have a torque capacity exceeding 1000 N·m.
The torque capacity is influenced by factors such as the size and material strength of the gears, the quality of the bearings, and the overall design and construction of the gearbox.
