Generally, Heavy Duty Trucks are used for transportation purpose of cargo with heavy loads and therefore, require a robust steering control (i.e. lateral stability) all the time (especially when moving at a high speed or during cornering) in order to ensure safety of the on-board crew, loaded goods and vehicle itself. Generally the steering system of the trucks is hydraulically assisted and this assistance is provided by a hydraulic pump which is driven by the main engine. Now the problem is, if this engine fails for any reason then there will be no more hydraulic assistance and it might put in a dangerous situation because it will be very difficult to handle that much load mechanically. Therefore to cope with this problem, an auxiliary hydraulic assistance is introduced with minimum possible modifications in the existing steering system of the Truck.
An auxillary hydraulic pump (with output pressure >= system working pressure) will be used which could use the input power from the following available options:-
1. If using mechanical input, then input will be taken from the power divider of the power transmission system. Because if even the engine is failed but still it will be in the running position because it is connected to the wheels through shafts and the wheels are still moving due to inertia of the vehicle. It means this auxiliary assistance will be working all the time as the vehicle is moving so the emergency response time is even less than 0.5 sec.
2. If using electrical input, then input will be taken from the battery of the vehicle. But this is not a feasible option because we never know about the battery condition and for emergency response we have to use some control system therefore the mechanical input should be preferred.
The pump will be connected to the PTO (Power take off) of the power divider through a power transmission shaft. The end connections of this power transmission shaft should be provided with the universal joints in order to assimilate the vertical and lateral vibrations and movements and avoid any undesired failure.
This pump will be connected in parallel to the existing hydraulic circuit which will suck the working fluid from the reservoir and will supply it to the steering spool valve. It should be provided with a non-return valve in order to avoid flow from the main steering system to the auxiliary system in normal conditions. Furthermore, for reversal flow due to reverse movement of the vehicle, a uni-directional electromagnetic valve should be provided that will be operated with the reverse gear switch in order to avoid air locking in the auxiliary system.
What make it Novel?
Simplicity, easy manufacturing, safety and low cost make it a novel design.
All parts of the design are standards except the power transmission shaft which is very simple and can be produced with simple lath machine.
Where to apply?
1. Automotive Companies
3. Insurance Agencies