Land Vehicles with Hybrid Transmission
It is possible to adjust existing design of land vehicles to
make them driven not with mechanical transmission and drive-train, but with purely
hydraulic transmission or with a hybrid transmission – a combination of
hydraulic and mechanical power transmissions.
When axes of powered
wheels, or powered gears, driving the tracks of a vehicle, do not move
relatively to the body of the vehicle, like in a tractor with large wheels, or
in a tracked tractor, it is possible to have a dedicated hydraulic motor,
driving each such wheel or gear.
Traditionally, rotation
from a motor is transmitted to a pair of suspended powered wheels through
following mechanical drive-train:
wheel
half-axel
u-joint – drive-shaft – u-joint –
gear-box
half-axel
wheel
U-joints provide
flexibility of drive-train movement along the body of the vehicle, and the
gear-box, which contains differential, works together with two half-axels as
one inflexible axel.
It is possible to modify this power
transmission subsystem and drive each wheal with a dedicated hydraulic motor
(there is no need for a differential in such case). We would need two
drive-shafts and two gear-boxes, each drive-shaft passing rotation to its
gear-box from a dedicated hydraulic motor. In turn, rotation from a drive-shaft
is passed to only one wheel, through a connected half-axel. To make devices
between two wheels rigid, we need to rigidly connect two gear-boxes:
wheel
half-axel
u-joint – drive-shaft – u-joint –
gear-box
connector
u-joint – drive-shaft – u-joint –
gear-box
half-axel
wheel
When all wheels are powered and
driven with this kind of power transmission, turning of the vehicle could be
done with rotating of wheels on one side of the vehicle faster than wheels on
the other side. In this case, there is no need for special wheels, guiding the
turning of the vehicle.
Hence, when one deploys this kind
of Hybrid Transmission, it makes sense to have all wheels powered.
Alexander Liss 8/18/2019