TRACTOR HYDRAULIC PARTS
Hydraulic switch box is a compact device designed for heavy applications in agricultural and forestry machines, trucks with special bodies (e.g. fire trucks) and for military vehicles.
The device is housed in a compact aluminum housing allowing mounting the case in any position. This solution gives both high mechanical strength and effective heat dissipation. High power combined with several combinations of inputs and outputs allow the implementation of the most diverse applications with extreme simplicity.
In addition to the output split function, the hydraulic switch box allows you to increase or decrease the output speed and change their direction.
In practice, the switch box is a small adapter to the transmission, whose task is primarily to transfer power to the other axle (always to the front). At the same time, the hydraulic switch box mediates the transmis sion of torque to the rear axle. Inside the axle there is a gear (toothed or chain), which leads from the inside of the gearbox a second drive shaft towards the front axle. At the moment when the switch box has no additional mechanisms but one system, we talk about a system with an attached automatic or manual drive.
The input of the hydraulic switch box is connected to the output of an ordinary gearbox, both boxes are usually directly attached to each other (and even integrated in one housing), but they can also be completely separate - they are connected then with a short drive shaft.
In off-road vehicles, the switch box is usually equipped with a lever that allows the driver to choose between one-wheel drive (typically rear) and two-wheel drive, the same lever can also be used to enable / disable off-road gear ratios. There are also gearboxes realizing permanent drive on both axles, so that it is possible to use such a drive on paved roads, such a gearbox must have a central (inter-axle) differential mechanism, in off-road vehicles such gearboxes enable / disable the lock of your differential mechanism.
It is possible that there is a differential inside the switch box that differentiates the rotational speed of both the rear and front propeller shafts. In this situation, it is permanent four-wheel drive. When there is an additional gear in the switch box, then the device is called a reducer.
The reducer is a type of switch box. Proper transfer box is a more appropriate term for the reducer, because its task is not only to distribute four-wheel drive, but also to reduce all ratios in the drive system.