DESC:FIELD OF INVENTION :

The invention relates to steering stability system of a vehicle and more specifically for a three wheeled vehicle operable with a steering handle bar.

OBJECT OF THE INVENTION :

The steering stabilizing system has been introduced to reduce wobbling in the steering system for a conventional vehicle. The system aims to improve the handling and stability of the steering system, resulting in better handling of the conventional vehicle typically having a steering handle bar.

SUMMARY OF THE INVENTION :

The present solution is related to the steering system and it will aid in conventional vehicle handling and driver comfort as well. By implementing the invention concept in the conventional vehicle, we can reduce wobbling in the steering handle bar. It will ensure the passenger comfort as the handling issue is also resolved by reducing the wobbling.

The invention is illustrated in Fig. 1 to 5 wherein the steering wobbling controlling system as available in prior art and as made available as per invention is depicted as comparison.

Part no. Part names - Fig 5 of invention
I1 Lock Nut
I2 Cap
I3 Damper
I4 Nut flange
I5 Outer Tube
I6 Steering Shaft

Part no. Part names - Fig 5 of Prior art
P1 Lock Nut
P2 Nut
P3 Cap
P4 Steering Shaft

DESCRIPTION OF THE INVENTION :

The three wheeled vehicle with a handle bar steering system is a very common public transport vehicle in India. It typically has one front wheel with linkage (trailing and leading) suspension and two rear wheels attached to corresponding swinging arms that are pivoted to the frame.

The steering system consists of components that allow the driver to turn the front wheel of the vehicle i.e., its basic function is to allow the driver to safely and precisely steer the vehicle. Beyond this, the steering system also typically provides a way to reduce driver effort by making the act of steering the vehicle easier. The components of the steering system also absorb some of the road shock before it gets to the driver.

A three wheeler is accordingly a vehicle that runs on three wheels and often have a front single wheel and mechanics similar to that of a motorcycle and rear axle similar to that of a car but operable with a handle bar steering system.

Typically “wobble mode” occurs at lower speeds of such vehicles and the reason is mainly found to be from steering column flexibility and this is the major contributor for wobble instability in a three wheeled vehicle operable with a handle bar steering system.

Generally we have negligible vibration at steering from the wheel due to road surface which is controlled by fine tuning of suspension. Application of the concept is for passenger and commercial vehicle segment in India. The vehicle has been designed with different weight distribution ratio for passenger safety and comfort in comparison to non-electric vehicles. The load experienced at the front axle is less when compared to non-electric vehicle. Owing to lower front axle weight, steering wobbles at slow speed. This wobbling adds to driver discomfort which is experienced as ride discomfort by the passenger as a result of poor handling. To fix the wobbling at steering, the dampener has been introduced between chassis and steering system. In comparison to the existing system, the invention met the vehicle dynamic comfort with minimal modification by considering cost, weight, manufacturability and serviceability.

As detailed herein, three wheelers are steered by operating a handlebar so as to turn a front fork supporting a front wheel around a steering stem. The steering stem is attached and inserted into a head pipe located at the front end of a body frame. As per this invention steering damper arrangement is made between the chassis frame and the steering system and on the steering stem.

A damper made of nitrile butadiene rubber (NBR) is placed over the flange-nut in the assembly and tightened using the locknut till it compresses to a depth of 1.5mm. This causes the rubber damper to bulge radially between the outer tube and radial face of the flange nut. This reduces wobbling while maintaining steering articulation within required limit.

Flange nut is used to place the NBR dampener. The function of the flange nut is to tighten the bearing. Dampener is placed on the flange nut, which is located between dampener and outer tube radial face. Lock nut is converted as flanged lock nut by adding the flange which is used to tighten the dampener. A cap is placed over dampener then the lock nut is tightened until it butts on bearing nut. The dampener stiffness has been optimized by conducting vehicle tests.

In one aspect the invention relates to a steering damper attachment for a handlebar operated vehicle which comprises of a steering stem (I6) and a steering front fork tube (I5) of front wheel rotatable about said steering stem in conjunction with operation of said handle bar. The vehicle has a front end head pipe of the body frame into which the steering stem is inserted. The arrangement as per invention includes a flange nut and a NBR damper (I3) disposed compressingly above the said flange nut (I4) sandwiched between said steering front fork tube and said body frame. Further a cap disposed above NBR damper and a lock nut (I1) disposed above the cap (I2).

With this said arrangement is novel that compressed damper disposed between the steering front fork tube and frame is such that the damper bulges radially and thereby reduces the wobbling but essentially maintains steering articulation within predetermined safe limit.

Some of the novelty features of this invention are as follows :-

1. Steering wobbling dampener is introduced between Chassis Frame and Steering system to isolate it.
2. The compression of NBR rubber which is used to generate the required stiffness to isolate the wobbling which goes to steering from the road through the wheel.
3. The method is used to isolate the wobbling by introducing a single component with existing number of components.
4. The dampener location is crucial as it requires less modifications from the existing system.
The invention has been described as detailed above but various embodiments and variations are possible beyond the preferred embodiments disclosed in this document. All such variations and modifications as obvious to the skilled person is within the scope of this invention. The applicant intends to rely upon specifications and the drawings submitted along with the specification.
,CLAIMS:WE CLAIM :
1. A steering damper attachment for a handlebar operated vehicle comprising :

- a steering stem (I6),
- a steering front fork tube (I5) of front wheel rotatable about said steering stem in conjunction with operation of said handle bar,
- a front end head pipe of the body frame into which the steering stem is inserted,
- a flange nut,
- a NBR damper (I3) disposed compressingly above the said flange nut (I4) sandwiched between said steering front fork tube and said body frame,
- a cap disposed above NBR damper, and
- a lock nut (I1) disposed above the cap (I2),
the said arrangement characterized in the compressed damper disposed between the steering front fork tube and frame, which damper bulges radially thereby reducing the wobbling but maintaining steering articulation within predetermined safe limit.