INTRODUCTION
PRELIMINAR STUDIES AND CONSIDERATIONS
MAINTENANCE AND DAMAGE PREVENTION
WORK ON BASIC VEHICLE
MOUNTING AND CONSTRUCTION
POWER TAKE-OFF
ELECTRIC AND ELECTRONIC SYSTEMS
APPENDIX
202
Body Builder Manual Part II, Specific Book LCV
V1.0, February 2015
Main factors when choosing a suitable PTO
The main factors to observe when selecting a PTO are as follows:
- Engine revolutions.
- Direction of rotation of the engine.
- Permissible and required torques in PTO.
- Type of gearbox used in case of PTO dependent on the clutch.
- PTO installation point and the maximum bending moment.
- Long time of use: in this case, care must be taken with the high oil temperature
in the gearbox.
PTO transmission ratio (Z)
The transmission ratio can be defined as the relationship between the rotational
speeds of two gears connected to each other. Because of this relationship, different
rotation speeds can be achieved between the input and the output of the PTO.
With a transmission ratio
- Z ≥ 1 the speed is increased at the output.
- Z=1 no speed difference between the input and the output.
- Z ≤ 1 the speed is reduced at the output.
Fig. 6-151 SPBGC61_001 Different PTO transmission ratios
However, it must also be taken into account that, with a constant value of power
delivered, the applied torque will also change when the transmission ratio is
changed, since the power depends on torque and rotation speed. Because of this, it
is recommended that a scan should be run to check whether this newly applied
torque is able to achieve the necessary values to move the body´s equipment.
Z
PTO transmission ratio
n
angular velocity