DESC:“PRELOAD ADJUSTER FOR REAR SHOCK ABSORBER”
Field of the invention
The present invention relates to rear shock absorber, more particularly to a preload adjuster for the rear shock absorber.
Background of the invention
Motorcycle suspensions are designed so that the springs are always under compression, even when fully extended. Pre-load is used to adjust the initial position of the suspension with the weight of the motorcycle and rider acting on it. Preload adjuster compresses or extends on the spring depending on what the user is trying to accomplish.
The difference between the fully extended length of the suspension and the length compressed by the weight of the motorcycle and rider is called "total sag" or "race sag". Total sag is set to optimize the initial position of the suspension to avoid bottoming out or topping out under normal riding conditions. "Bottoming out" occurs when the suspension is compressed to the point where it mechanically cannot compress any more. Topping out occurs when the suspension extends fully and cannot mechanically extend any more. Increasing pre-load increases the initial force on the spring thereby reducing total sag. Decreasing pre-load decreases the initial force in the spring thereby increasing total sag. The sag is adjusted within the suitable range depending upon road conditions and riding style. Less sag improves turning ability but reduces overall stability while more sag improves overall stability but may reduce turning performance. Adjusting the sag within proper limits is the most important yet most overlooked thing because of the rider’s unawareness and complexity in preload adjustment feature. In majority of the cases pre-adjustment of spring is made as a redundant feature due to the difficulty in operating the adjuster.
Accordingly, there exists a need to provide a user friendly preload adjuster for the rear shock absorber, which overcomes the drawbacks of prior arts.
Objects of the invention
An object of the present invention is to provide user friendly device for preload adjustment of the rear shock absorber.
Another object of the present invention is to enable the vehicle user/rider to adjust the sag within suitable limits so as to increase the rider’s comfort.
Summary of the invention
The present invention provides a system for adjustment of preload of a rear shock absorber of a vehicle. Adjustment of sag within proper limits is necessary for rider’s comfort. The user friendly system of the present invention for adjusting sag and increasing rider’s comfort comprises of a remote adjuster unit equipped with an adjuster knob and located at an easy to reach place on the vehicle. The rear shock absorber of a vehicle is provided with a spring adjuster for adjusting the height of the suspension spring. In the present invention, the spring adjuster is configured with slots provision for adjustments of spring height with defined angle of movement. The spring adjuster and the adjuster knob are connected by means of a adjuster cable, with two free ends of the adjuster cable locked with the adjustment knob and centrally folded loop portion of the adjuster cable locked with the spring adjuster. When the adjustment knob is twisted in clockwise or anticlockwise direction, the cable is pulled, which in turn rotates the spring adjuster in clockwise or anticlockwise direction with partially expanding or contracting the spring and in turn, adjusting the spring preload. Thus, the rider can easily adjust the height of the suspension spring and in turn the preload value, by twisting the adjuster knob.
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 perspective view of rear shock absorber with preload adjustment means, in accordance with the present invention;
Figure 2 shows the perspective view of the spring adjuster of the preload adjustment means, in accordance with the present invention;
Figure 3 shows the perspective view of the preload adjustment knob, in accordance with the present invention;
Figure 4 shows the perspective view of the adjuster cable, in accordance with the present invention;
Figure 5 shows preload adjustment knob twisted in clockwise direction to increase the preload on shock absorber, in accordance with the present invention; and
Figure 6 shows preload adjustment knob twisted in anticlockwise direction to reduce the preload on shock absorber, in accordance with 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.
In one aspect, the present invention provides a rear shock absorber with a remote preload adjuster. The remote preload adjuster provided by the present invention is user friendly and it enables the user to adjust the sag within suitable limits so as to increase the rider’s comfort.
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.
Referring to Figures 1 to 6, rear shock absorber (100) with a remote preload adjuster unit (20) in accordance with the present invention is shown. The rear shock absorber (100) comprises a damper (10), constructed to be interposed between a vehicle body (not shown) and a wheel hub (not shown) of the vehicle. Upper end (70) of the damper (10) is connected to the vehicle body and lower end (80) of the damper (10) is secured to the wheel hub. The shock absorber further comprises a suspension spring (60) coaxially suspended around the damper (10). A spring adjuster (50) is configured with a plurality of spring adjuster slots (50B). More particularly, the spring adjuster (50) is configured with at least three adjuster slots (50B). The spring adjuster (50) supports the spring (60) at one end thereof. The spring is partially expanded or contracted on rotating the spring adjuster (50) in clockwise or anticlockwise direction. Thus, height and preload of the spring (60) can be increased or reduced by rotating the spring adjuster (50) in clockwise or anticlockwise direction. The spring adjuster slots (50B) are provided for adjusting the spring height with defined angle of movement. The rear shock absorber (100) further comprises a preload adjuster unit (20) mounted remotely on the vehicle, at a position suitable for the rider. The preload adjuster (20) comprises of an adjuster knob (30) having two adjuster knob slots (30B). The preload adjuster (20) also comprises an adjuster cable (40) having two free ends centrally folded to form a loop. Bothe the free ends are configured with a first set of locking means (40A) and the loop is configured with a second set of locking means (40B). The first set of locking means (40A) is configured to lock with the corresponding adjuster knob slots (30A) and the second set of locking means (40B) is configured to lock with the corresponding adjuster slots (50B);
In an embodiment, rotating the adjuster knob (30) in clockwise direction pulls the adjuster cable (40), rotates the spring adjuster (50) in clockwise direction and increases the preload on spring (60).
In another embodiment, rotating the adjuster knob (30) in anticlockwise direction pulls the adjuster cable (40), rotates the spring adjuster (50) in anticlockwise direction and reduces the preload on spring (60).
The remote adjuster unit (20) is mounted at a suitable position on the vehicle and the adjustment knob (30) is located in an easy to reach place on the vehicle and spring preload changes are made by twisting the knob.
Advantages of the invention:
• The product feature can be utilized for better ride comfort.
• The rider can easily adjust the suspension preload.
• No additional tool required for suspension preload adjustment.
• User friendly and less time consuming option.
• Preload adjuster unit can be an additional selling feature.
The foregoing objects of the invention are accomplished and the problems and shortcomings associated with prior art techniques and approaches are overcome by the present invention described in the present embodiment. Detailed descriptions of the preferred embodiment are provided herein; however, it is to be understood that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure, or matter. The embodiments of the invention as described above and the methods disclosed herein will suggest further modification and alterations to those skilled in the art. Such further modifications and alterations may be made without departing from the spirit and scope of the invention. ,CLAIMS:We claim:
1. A preload adjuster (20) for a rear shock absorber (100) of a vehicle, the rear shock absorber (100) having a damper (10) interposed between a vehicle body and a wheel hub of the vehicle; a spring (60) coaxially suspended around the damper (10); a spring adjuster (50) configured with a plurality of spring adjuster slots (50B) and supporting one end of the spring (60) in such a way that rotating the spring adjuster (50) in any one of the clockwise and anticlockwise direction changes the height of the spring (60) and the preload thereof; and a preload adjuster (20) comprising:
an adjuster knob (30) configured with two adjuster knob slots (30A); and
an adjuster cable (40) having two free ends centrally folded to form a loop, both free ends configured with a first set of locking means (40A) and the loop configured with a second set of locking means (40B), the first set of locking means (40A) being configured to lock with the corresponding adjuster knob slots (30A) and the second set of locking means (40B) being configured to lock with the corresponding adjuster slots (50B);
wherein the adjuster knob (30) is rotated in any one of the clockwise and anticlockwise direction, thereby pulling the adjuster cable (40) and rotating the spring adjuster (50).
2. The preload adjuster (20) for a rear shock absorber (100) as claimed in claim 1, wherein the spring adjuster (50) is configured with at least three adjuster slots (50B).
3. The preload adjuster (20) for a rear shock absorber (100) as claimed in claim 1, wherein the preload adjuster (20) is remotely mounted on the vehicle.
4. The preload adjuster (20) for a rear shock absorber (100) as claimed in claim 1, wherein rotating the adjuster knob (30) in clockwise direction pulls the adjuster cable (40), rotates the spring adjuster (50) in clockwise direction and increases the preload on spring (60).
5. The preload adjuster (20) for a rear shock absorber (100) as claimed in claim 1, wherein rotating the adjuster knob (30) in anticlockwise direction pulls the adjuster cable (40), rotates the spring adjuster (50) in anticlockwise direction and reduces the preload on spring (60).
Dated this 24th day of August, 2017

Prafulla Wange
(Agent for the applicant)
(IN/PA-2058)