A lot of people use terms like final drive, travel motor, track drive, and hydraulic motor interchangeably ... but are they really the same?
Here are a few other Shop Talk Blog posts you might find interesting ...
- High Points in the History of Construction Equipment
- Short History of Motor Graders
- Ultimate Glossary of Terms for Hydraulic Motors
In this Shop Talk Blog post, we'll go all the way to some of the early patents for things like hydrostatic vehicle drive systems to bring you some solid answers.
Hydraulic Drive Systems
A good place to start this discussion would be with explaining what a hydraulic drive system is. In a typical hydraulic drive system, you have ...
- A power source (usually an internal combustion engine) that powers a hydraulic pump
- A hydraulic pump that provides the fluid that actuates the hydraulic motor
- A hydraulic motor provides power to a planetary gear system
- The speed-reducing planetary gear set (sometimes called a planetary hub or gear hub) transforms the power into torque and transmits it to a sprocket (in the case of a track driven machine) or to the wheels (or through a system that results in wheel motion, as in a skid steer loader)
Final Drive Motors
Strictly speaking, the final drive motor is the combination of a hydraulic motor with a planetary gear system. The hydraulic motor may be referred to as the hydraulic hub or hydraulic side while the gear system is the gear hub. The final drive may also be referred to as the planetary gear final drive unit or the planetary final drive.
The term final drive (by itself) is often used to refer to final drive motors, but, strictly speaking, actually refers to the speed-reducing, torque-multiplying gear system.
Travel Motors
Technically, the term travel motor is used to differentiate the motors that power the wheels or tracks from the swing motor in machines such as excavators. By that definition, a final drive is synonymous with a travel motor, although the term travel motor may be used more often with excavators.
Wheel Motors and Track Motors
The terms wheel motor and track motor refer to two different type of drive system: wheel-based and track-based, respectively. They do both refer to final drive motors, however.
Conclusion
The good news is that when you call us at Texas Final Drive (or Final Drive Parts), we know what you mean even if you don't use the right technical jargon. We know our parts and systems well enough that we can help you figure out what you need -- whether its a final drive motor for a skid steer loader, a wheel motor for your tractor, or a track drive for your mini-excavator.
