PTO Gearboxes
PTO or Speed up gear boxes are mainly used on agricultural tractors where more hydraulic power is necessary than the system on the tractor can provide.
The quick release coupling on the gear box attaches to the tractor PTO shaft and steps up the PTO speed to one much more suited to the efficient speed of a hydraulic 
pump. A Gear pump is fitted to the other part of the gear box.
The Power Take-Off, most commonly described by its acronym, PTO, is a common kind of mechanical power delivery in the mobile machine market. The PTO can be a way of transferring high power and torque from the engine (usually via the transmitting) of trucks and tractors. In combination with gearboxes and pump mounts, almost any kind of mechanical power tranny is possible.
There are three common power take-off methods in the mobile machine market; tractor style, truck transmission style and engine crankshaft-driven, although the latter is not commonly known as a PTO. The crankshaft-driven method of power transmission is frequently utilized for hydraulic pumps installed to leading of an on-highway truck, such as a plow/spreader or cement mixer. A little shaft with U-joints attaches to a yoke coupler to carefully turn the pump. This configuration of drive isn’t generally referred to as a PTO, however.
The tractor PTO goes back pretty much so far as tractors. Many early PTOs were driven from the tranny, which being proudly located behind the tractor, permits easy location of an output shaft. The transmission type of PTO is only engaged when the tranny clutch is also engaged, and is coupled directly to transmission, to ensure that when the clutch is depressed, the PTO isn’t driven.
If the transmission is driving the wheels, then your transmission PTO is turning. This does mean the apply can backward-power the transmission as well when the clutch is depressed, such as down a hill or if the attachment has a system with high rotational inertia, resulting in surging of the drive tires. This was prevented by the addition of a devoted overrunning clutch for the PTO, which prevents torque from getting applied in the contrary direction.
A live PTO often uses a transmission clutch with two levels. The first stage of the clutch functions the driven part of the tranny, and the second stage of the clutch settings the engagement of the PTO. This method allows independent control of the tranny, to ensure that the PTO maintains operation regardless of tranny clutch activity, including stopping of the tractor itself. For a tractor with a mower attachment, for instance, this is a minimum requirement; you can’t possess the mower turn off when you feather the clutch up a hill and around a tree.
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