DESC:“SYSTEM FOR ADJUSTING DAMPING FORCE IN A FRONT FORK SUSPENSION”
Field of the invention
The present invention relates to a front fork suspension and more particularly it relates to a system for adjusting damping in the front fork suspension to a normal mode or a comfort mode.
Background of the invention:
Conventional front forks are with a preset damping forces which is decided by the piston hole size and valve mechanism assembled in front fork. High end bikes are well equipped with advanced systems on improved engines, light weighting, and aerodynamics and so on. But suspensions are still with limited improvements like few of them were inverted front forks for rigidity, noise elimination, but there had not been much developments on ride comfort or fine tuning damping.
Accordingly, there exists a need for improving the ride comfort of two wheelers and necessary adjustment provisions for rider to choose and vary the type of ride.
Objects of the invention
An object of the present invention is to provide a system for adjusting damping in the front fork suspension, without changing the external structure and mounting of the front fork.
Another object of the present invention is to provide a user friendly method for adjusting damping in the front fork suspension.
Still another object of the present invention is to improve the ride comfort of two wheelers as per the road conditions.

Summary of the invention
The present invention provides a system for adjusting damping force in a front fork suspension. The internal configuration of the front fork is modified with a specially designed cartridge unit fitting within the inner tube of front fork. The cartridge unit comprises of a throttle valve with a throttle pin that opens or closes the additional oil flow path through the throttle valve. The opening and closing of additional oil path is done by actuating a shaft connecting the throttle pin to the actuating unit fitted at the top of the inner tube. The damping force can be adjusted to a comfort mode or a normal mode by opening or closing the throttle valve through the actuating unit, either manually or electrically.
Brief description of the drawings
The objects and advantages of the present invention will become apparent when the disclosure is read in conjunction with the following figures, wherein
Figure 1 shows a cross sectional view of a front fork with blown up section of a system for adjusting damping force in a front fork suspension, in accordance with the present invention;
Figure 2 shows a cross sectional view of a motor mounting mechanism of the system for adjusting damping force in a front fork suspension, in accordance with the present invention;
Figure 3 shows a detailed cross sectional view of a throttle valve inside the front fork suspension, in accordance with the present invention; and
Figure 4 shows a cross sectional view of a front fork with blown up section of an adjusting knob, in accordance with one of the embodiments of the present invention.
Detailed description of the invention
The foregoing objects of the present invention are accomplished and the problems and shortcomings associated with the prior art, techniques and approaches are overcome by the present invention as described below in the preferred embodiments.
The present invention provides a system for adjusting damping force in a front fork suspension. Internal configuration of the front fork is modified without changing the external structure and mounting of the front fork. The present invention provides an easily adjustable system to improve the ride comfort of two wheelers as per the road conditions. In normal mode, oil passes through the piston holes creating normal damping force. The system of present invention provides an additional path for oil to pass through, thereby reducing the damping force.
The present invention is illustrated with reference to the accompanying drawings, wherein numbers indicated in the bracket represent the components of the invention throughout the description.
Number Description Number Description
100A Actuating unit 40A Piston openings
10 Outer tube 45 Motor
15 Inner tube 50 Protection cap
20 Cartridge unit 55 Bolt cap
25 Throttle valve 60 coupler
25A Valve openings 65 Shaft
30 Throttle pin 70 Adjustment knob
40 Piston
Referring to figures 1 to 3 a system (100) for adjusting damping force in a front fork suspension (hereinafter, “the system (100)”) in accordance with the present invention is shown. The system (100) according to present invention comprises of an outer tube (10) having one end closed and the other end open, an inner tube (15) partially mounted within the outer tube (10). The inner tube (10) and the outer tube (15) are telescopingly movable with respect to each other. Upper end of the inner tube (15) is closed with a bolt cap (55) housing an actuating unit (100A).
A cartridge unit (20) defining an oil reservoir is housed within the inner tube (15). The cartridge unit (20) is fitted with a throttle valve (25) there within, having a throttle pin (20) and configured with a plurality of valve openings (25A). A shaft having one end connected to the actuating unit (100A) and the other end is connected to the throttle pin (30) and then to a piston (40). The shaft (65) upon actuation by the actuating unit (100A) is capable of moving the throttle pin (30) to and fro thereby closing and opening the oil flow through the valve openings (25A). The piston (40) is configured with a plurality of piston openings (40A) and is mounted within the cartridge unit (20).
The plurality of throttle openings (25A) provides an optional oil path to adjust the front fork damping with different ride comfort. During sports mode (or original position, normal mode), when a higher damping force is required, oil path through throttle unit (25) is blocked by moving the throttle pin (30) to close the plurality of valve openings (25A) and allowing the oil to pass only through piston orifices (40A). In comfort mode, additional oil path through throttle (25) is opened by moving the throttle pin (30) to open the plurality of valve openings (25A). In comfort mode, oil also passes through the piston orifices (40A).
In an embodiment, the actuating unit (100A) is an electrically operated unit comprising a motor (45) with a protection cap (50) housed within the bolt cap (55). In this arrangement, drive shaft of the motor (45) is connected to the shaft (65) through a coupler (50).
In another embodiment, he actuating unit (100A) is manually driven unit, provided with an adjustment knob (70) for actuating the shaft (65) to the desired position.
In this way, based on the hard and soft requirement of the rider, throttle pin (30) is operated to quickly set the ride comfort. User friendly knobs (not shown) are provided to ease out the adjustment of the damping forces.
Advantages of the invention:
• Damping force adjustment provision is made possible without changing the external structure and mounting of the Front fork
• User friendly adjustment makes rider to quickly tune to the required ride comfort.
The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, and to thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but such omissions and substitutions are intended to cover the application or implementation without departing from the spirit or scope of the claims of the present invention.
,CLAIMS:We claim:
1. A system (100) for adjusting damping force in a front fork suspension, the system (100) comprising:
an outer tube (10) having one end closed and the other end open;
an inner tube (15) partially mounted within the outer tube (10), the inner tube (10) and the outer tube (15) being telescopingly movable with respect to each other; upper end of the inner tube (15) fitted with a bolt cap (55) housing an actuating unit (100A)
a cartridge unit (20) defining an oil reservoir and housed within the inner tube (15), the cartridge unit (20) being fitted with a throttle valve (25) there within, the throttle valve (25) having a throttle pin (30) capable of moving to and fro to close and a plurality of valve openings (25A) configured therein; and
a shaft (65) having one end connected to the actuating unit (100A) and the other end connected to a piston (40) through the throttle valve (25), wherein the piston (40) is configured with a plurality of piston openings (40A) and the shaft (65) on actuation by the actuating unit (100A) is capable of moving the throttle pin (30) to and fro;
wherein,
during normal mode, the throttle pin (30) is moved to close the plurality of valve openings (25A) and allowing the oil to pass only through piston orifices (40A) during compression stroke, thereby maintaining the damping force, and
during comfort mode, the throttle pin (30) is moved to open the plurality of valve openings (25A) to allow the oil to pass therethrough during compression stroke, thereby lowering the damping force.
2. The system (100) as claimed in claim 1, wherein the actuating unit (100A) is an electrical operated unit having a motor (45) with a protection cap (50) housed within the bolt cap (55) and the shaft (65) connected to the drive shaft of motor (45) through a coupler (50).
3. The system (100) as claimed in claim 1, wherein the actuating unit (100A) is a manually operated unit having an adjustment knob (70) provided on upper end of the inner tube (15).
Dated this 27th day of December 2017,

Prafulla Wange
(Agent of Applicant)
(IN/PA-2058)