PTO Gearboxes
PTO or Speed up gear boxes are primarily applied to agricultural tractors where more hydraulic power is required than the system on the tractor can offer.
The quick release coupling on the apparatus 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 apparatus box.
The Power Take-Off, most commonly described by its acronym, PTO, is a common form of mechanical power delivery in the mobile machine marketplace. The PTO is usually a method of transferring high power and torque from the engine (generally via the transmitting) of trucks and tractors. In mixture with gearboxes and pump mounts, nearly any type of mechanical power transmission is possible.
There are three common power take-off methods in the mobile machine market; tractor style, truck transmission design and engine crankshaft-powered, although the latter isn’t commonly known as a PTO. The crankshaft-driven method of power transmission is frequently used for hydraulic pumps mounted to the front of an on-highway truck, like a plow/spreader or cement mixer. A small shaft with U-joints attaches to a yoke coupler to carefully turn the pump. This configuration of drive is not generally referred to as a PTO, however.
The tractor PTO goes back pretty much as far as tractors. Most early PTOs were driven from the tranny, which being proudly located at the back of the tractor, allows for easy location of an result shaft. The transmission type of PTO is engaged when the transmitting clutch is also engaged, and is certainly coupled directly to transmission, to ensure that when the clutch is certainly depressed, the PTO isn’t driven.
If the transmission is driving the wheels, then the transmission PTO is turning. This also means the implement can backward-power the transmission as well when the clutch is certainly depressed, such as for example down a hill or if the attachment includes a system with high rotational inertia, resulting in surging of the drive tires. This was avoided by the addition of a dedicated overrunning clutch for the PTO, which prevents torque from being applied in the opposite direction.
A live PTO often uses a tranny clutch with two phases. The initial stage of the clutch works the driven part of the transmitting, and the next stage of the clutch controls the engagement of the PTO. This method allows independent control of the transmitting, 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 the very least requirement; you can’t possess the mower switch off when you feather the clutch up a hill and around a tree.
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