There are several types of rollers used on cotton pickers, each serving a specific function in the harvesting process:

1. In-feed rollers: These rollers are located at the front of the cotton picker and help to guide the cotton plants into the picking unit. They can be adjustable to accommodate different plant heights and ensure a smooth and steady flow of cotton into the picking mechanism.

2. Doffer rollers: Doffer rollers are located within the picking unit and are responsible for removing the picked cotton from the spindles. They help to separate the cotton fibers from the plant material and facilitate the transfer of the harvested cotton to the collection bins or baskets.

3. Lint cleaner rollers: After the cotton has been picked and removed from the plant, lint cleaner rollers help to further clean and remove any remaining impurities, debris, or trash from the cotton fibers. This helps to improve the quality of the harvested cotton.

4. Transport rollers: These rollers assist in moving the harvested cotton through the various stages of the picking unit and into the collection bins or baskets. They help to ensure a continuous flow of cotton through the machine during the harvesting process.