DESC:FIELD OF INVENTION

The present invention relates to handlebars, particularly to the bicycle handlebars. It also relates to the means for absorbing shock and reducing the vibration transmitted in bicycles.

BACKGROUND OF THE INVENTION

The rider is in direct contact with the handlebar and so reducing the vibrations that are transmitted to the handlebar will effectively free the rider of exposure to vibrations that may cause any discomfort to the rider in the long term. Bicycles are an efficient, inexpensive and environment friendly means of converting mechanical energy into another form, in order to produce self-propelled motion. The biggest problem for a cyclist is the vibration that the body of the cyclist has to absorb. The bumps and jolts on the terrain of the cyclist are directly transmitted to the tires, which are passed on to the front forks and to the handlebar, to the cyclist. The amplitude and frequency of these vibrations are not amply dampened by the tires, shock absorption systems, and other parts of the bicycle, and this is particularly of concern in mountain terrain and off- road bicyclists. Long distance riders are also affected by the vibrations, despite the amplitude being inappreciable, as the duration of exposure is high. The joints of the cyclists are thus affected causing the rider to detract from the pleasure of cycling. In the worst case scenario, the rider is forced to abstain completely from cycling.

Vibration reduction mechanisms in handlebars have been researched and materialized. It usually comprises of some element in tension to stiffen the handlebar. Also, mechanisms comprising of a curved strip of flexible material which is adapted at one end thereof, to be fixedly mounted on the head of the support bracket and at the other end thereof to be fixedly attached to the handlebar itself on both sides of the bracket clamp supporting the handlebar as shown in Fig 12. These mechanisms are oversized and usually are located outside the handlebar. Such mechanisms slap on additional weight to the bicycle, which is undesirable. The amount of vibration that such systems attenuate is also limited. Thus, present systems are inadequate or are of little value for vibration reduction in the present day and age.

SUMMARY OF THE INVENTION

The invention consists of a handlebar which is directly connected to the front fork of the cycle. The stem 13 supports two angled tubes which is attached at the other end to the base of the handlebar. This design of the integrated handlebar and stem increases the stiffness of the handlebar, which in turn reduces the vibrations transmitted from the base. The section modulus of the handlebar is also higher for the cross section as shown in Fig. 6. It is also aimed to dissipate vibration and shocks in the handlebar by providing inserts of high damping capacity, to reduce the amount of vibration that the riders must otherwise endure. The invention includes handlebars that are mounted directly onto the front fork of the bicycle with the damping inserts inside the handlebar. These damping inserts absorb the vibrations that are transmitted from the roads to the front fork which are then passed on to the handlebar. The y shaped design allows for three points of contact on the handlebar and allows for faster attenuation of vibration. The damping inserts are either inserted as a solid block of damping material, or hollow or in some structure so that the damping capacity is increased and the weight of adding such a setup is minimal. The structure may be in a form, as shown in Fig. 11, comprising of, hexagonal, over expanded, reinforced hexagonal, square, flex core, double flex core, or cross core structure. The aforementioned structure sheets may be rolled to fit into the hollow handlebar. The handlebar may also contain a set of end caps to dampen the vibrations. The aforementioned end caps may be made of a material comprising of viscoelastic polymers or elastomers. This damping technique does not cause any change in the natural posture of the cyclist while riding nor does it require any variation in the cycle design. The embodiment is compact, light in weight and may be adapted to suit any handlebar.

BRIEF DESCRIPTION OF DRAWINGS

Fig. 1 is a front perspective view of the complete handlebar
Fig. 2 is the rear perspective view of the complete handlebar
Fig. 3 is the front view of the complete handlebar
Fig. 4 is the top view of the complete handlebar
Fig. 5 is the perspective view of a section of the handlebar from the side
Fig. 6 is the cross section of the handlebar as shown in fig 5
Fig. 7 is the handlebar with a solid damping insert.
Fig. 8 is the handlebar with an annular damping insert.
Fig. 9 is the cross section of the handlebar with the hollow damping insert as shown in fig. 8
Fig. 10 is the handlebar with a solid damping insert made of various structures
Fig. 11 are the possible structures for the damping insert as shown in fig. 10
Fig. 11a is a hexagonal structure
Fig. 11b is an over expanded hexagonal structure
Fig. 11c is a reinforced hexagon structure
Fig. 11d is a square structure
Fig. 11e is a flex core structure
Fig. 11f is a double flex core structure
Fig. 11g is a cross core structure
Fig. 12 is the prior art consisting of a handlebar with a damping element 31 attached to the head 35 on one end and the other end 36 is clamped to the handlebar using screws 37. Fig. 13 is the isometric view of the curved strip 31 of metal depicting the slot 33 meant for attaching to the bicycle stem and the strip bifurcating into two to allow the curved strip 31 to be bolted to the handlebar.
Fig. 14 is the amplitude vs. time plot of the handlebar.
Fig. 15 is the amplitude vs. time plot of the handlebar with a viscoelastic polyurethane damping insert.

DETAILED DESCRIPTION OF THE INVENTION

Fig. 1 illustrates the bicycle handlebar assembly. The handlebar can be manufactured from a material consisting of carbon steels, elastomers, brass, bronze, or aluminum. Alternatively, the handlebar can be formed from a composite material, such as Kevlar or carbon fiber that provides for significant strength, while reducing the overall weight of the bicycle. The handlebar could also be made from a combination of the above and other materials. The handlebar is supported by a central stem 13 and two laterally projecting tubes on the right 11 and left 12. The central stem 13 is joined to the handlebar by a plate 14. The tubes and the plates are welded together. The central stem 13 is of a larger diameter at the upper end of the stem and the diameter is reduced towards the lower end and the stem fits into the front fork of the bicycle. The plate 14 connects the stem 13 and the handlebar 10. The plate 14 has a hole located centrally. The tubes 11, 12 connecting the stem and the handlebar are designed in such a way that the loads are transmitted laterally. The angle between the above said tubes may range between 30-50 degrees from the stem, which is designed for maximum stiffness and vibration attenuation.

Fig. 2 is the rear perspective view of the handlebar assembly. It can be clearly seen that the handlebar tube 10 is hollow. The shape of the plate 14 is as illustrated. Fig. 3 is the front view of the integrated handlebar, shows the ‘Y’ shaped design of the handlebar. Fig. 4 is the top view of the handlebar assembly.

Fig. 5 is an illustration of a portion of the handlebar. The cross section of the handlebar shown in Fig. 5 is shown in Fig. 6.
Fig. 7 illustrates a damping member 21 is placed within the handlebar tube. The illustrated damping member is substantially cylindrical in that it includes an outer surface that substantially matches the contour of the inner surface of the handlebar tube. An adhesive may be used to bond the outer surface of the damping member to the inner surface of the handlebar. In constructions that employ an adhesive, one or both of the mating Surfaces may be roughened or grooved to provide additional surface area to improve the bond between the surfaces. In other constructions, a close fit or an interference fit may be established between the damping member and the handlebar. The damping ratio of the handlebar is increased by around 84 times by filling the handlebar in with a viscoelastic polyurethane material. The value of damping ratio of the handlebar after it is filled with silicone rubber insert increases the damping ratio 14 times.

The aforementioned damping member, can alternatively be annular in structure 22 as shown in Fig. 8, and can be inserted into the handlebar with the outer surface in contact with the contour of the inner surface of the handlebar. The cross section of the handlebar with an annular damping insert is shown in Fig. 9. In the case of an annular insert of viscoelastic polyurethane material, the damping ratio is augmented around 40 times.

The damping member can also be structurally modified to various structures 23. The various structures consists of hexagonal, over expanded hexagonal core, reinforced hexagonal, square core, flex core, double flex core, or cross core as shown in Fig. 11a-g.

Fig. 12 depicts a damping system in the handlebar where a curved metal sheet 31 is attached to the handlebar 38 at one end and the stem 34 at the other end. Tension is maintained in the plate which in turn reduces the vibration. The curved plate 32 is fixed at the end in contact with the handlebar using screws 37. The slot 33 facilitates the attachment of strip 31 to a range of handlebar mounting configurations.
Fig. 14 is the amplitude vs. time plot of the handlebar made of SAE1010 steel assuming initial loading conditions. Fig. 15 is the amplitude vs. time plot for the improved handlebar with a viscoelastic polyurethane damping material inserted into the handlebar as shown in Fig. 7.

In one aspect the invention describes clearly a handle bar arrangement of a bicycle wherein the shock absorption of the bicycle is adjustably reduced by transmitting the loads laterally.

The said arrangement comprising of:-
- a handle bar (10) of the cycle with a first laterally projecting tube (11) with its one end is fixed on one side of the handle bar (10). A second laterally projecting tube (12) with its one end is fixed on other side of the handle bar (10) and spaced away from the first tube (11). The arrangement includes a central stem (13) at its lower end adapted to fit into front fork of the bicycle. It has a diameter which at its lower end is adapted for fitting into front fork. This diameter at its lower end is lesser than its diameter at its upper end. The said central stem arranged centrally between the two projecting tubes (11,12). The arrangement also includes a connecting plate (14) having a central hole fixedly connecting the central stem (13) to the handle bar (10).The arrangement is such that the remote end of the first laterally projecting tube (11) is fixedly connected to the underside of the handlebar (10) at an angle between 30-500 from the central stem (13). Similarly the remote end of the second laterally projecting tube (11) is also fixedly connected to the underside of the handlebar (10) at an angle between 30-500 from the central stem (13). The said arrangement is novel in that the handle bar has a “Y” shape from the front side of bicycle with the arrangement of the stem and two projecting tubes combined.

In another aspect of the invention the said handle bar tube is hollow, preferably an annular oval.

The invention may also include liquids such as water and different types of oil that can be filled inside the handlebar to increases the dampening dramatically. On filling the oval handlebar with water, a significant increase in the damping is achieved. Further, on filling with SAE20 oil, an increase in the damping of almost 3 times that of water is achieved, the filling of liquids could be done in smaller capsules which further are used as inserts into the handle bar or could be directly filled into the handlebar sealing the both the ends of the handlebar. The capsules could be made of a flexible material that expands when filled with various liquids and to have complete contact with the inner surface of the handlebar.

The invention may also include arranging a damping member (21) disposed within the handle bars extending through partially or entirely through length of the handle bar and such that the outer contour of damping member (21) matches the inner contour of handle bar and the damping member (21) may be bonded within the handle bar with an adhesive.

Further the disclosure teaches that the arrangement of the outer surface of the damping member (21) is not smooth but possesses uneven surfaces such as roughened or grooved to enable and improve adhesion & damping.

The damping member of polymer such as polyurethane or viscoelastic polyurethane material or a silicon rubber insert with a modulus of elasticity sufficiently low to allow it to cause damping to absorb vibration from the road surface is most preferred.

Further the shape of damping member may be variable - annular, hexagonal mesh, reinforced hexagon, over expanded hexagon, square, flex core, double flex core or cross core and all of it is based on the contour, shape & configuration of the handle bar.

Further such damping members may not be of just single layer but may be of more than one layer of damping materials with various combinations including liquids. This is based on the amount and type of damping that is demanded.

The damping member insert includes a stopper at the extremity of the handle bar to ensure rigidity and reliability.

THE ADVANTAGES OF THE INVENTION ARE

It is a handlebar comprising an annular oval body, wherein the handlebar is made from a material consisting of carbon steels, elastomers, brass, bronze, aluminum or something other than carbon steels, elastomers, brass, bronze, aluminum. The handlebar consists of two laterally projecting tubes supporting the handlebar and a plate connecting the handlebar to the stem. The range of the angle between the stem and the laterally projecting tubes may range from 30-50 degrees.

It is a handlebar comprising an annular oval body wherein said annular body has an insert extending from the internal cylindrical surface of said body, wherein said insert is made of a material belonging to the group composed of polymers, or other materials even liquids. The aforementioned insert, comprising of polyurethane or other viscoelastic polymers, may have a modulus of elasticity sufficiently low to allow it to cause damping to absorb vibrations from the road.

The insert in one embodiment is annular.
The insert in second embodiment is of hexagonal mesh structure.
The insert in third embodiment is of a reinforced hexagon structure.
The insert in fourth embodiment is of an over expanded hexagonal structure.
The insert in fifth embodiment is of a square structure.
The insert in sixth embodiment is of flex core structure.
The insert in seventh embodiment is of double flex core structure.
The insert in eighth embodiment is of a cross core structure.
The insert in ninth embodiment is made of different layers in damping materials.

The insert in tenth embodiment is made of damping Liquids.

The hollow insert described above will include a stopper at the extremity of the handlebar, which comprises an oval plug having a hollow stem fitting inside a tubular end of the handlebar and provided with an expandable conical element capable of expanding said hollow stem to press against the internal wall of said tubular end of the handlebar.

The insert described above may extend through the length of the handlebar tube 10 or may extend only to a part of the handlebar.

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 provisional specification and the drawings submitted along with provisional specification
,CLAIMS:WE CLAIM:

1) A handle bar arrangement of a bicycle wherein the shock absorption of the bicycle is adjustably reduced by transmitting the loads laterally, the said arrangement comprising of:-
- a handle bar (10),
- a first laterally projecting tube (11) with its one end fixed on one side of the handle bar (10),
- a second laterally projecting tube (12) with its one end fixed on other side of the handle bar (10) and spaced away from the first tube (11),
- a central stem (13) at its lower end adapted to fit into front fork of the bicycle, and having a diameter at its lower end for fitting into front fork and which diameter at its lower end is lesser than its diameter at its upper end, the said central stem arranged centrally between the two projecting tubes (11,12),
- a plate (14) having a central hole fixedly connecting the central stem (13) to the handle bar (10),
- wherein the remote end of the first laterally projecting tube (11) is fixedly connected to the underside of the handle bar (10) at an angle between 30-500 from the central stem (13)
- wherein the remote end of the second laterally projecting tube (11) is fixedly connected to the underside of the handle bar (10) at an angle between 30-500 from the central stem (13)
- the said arrangement characterized in that the handle bar has a “Y” shape from the front side of bicycle with the arrangement of the stem and two projecting tubes combinedly.

2) The handle bar arrangement of a bicycle as claimed in claim 1, wherein the said handle bar tube is hollow, preferably an annular oval.
3) The handle bar arrangement of a bicycle as claimed in claims 1 & 2, wherein a damping member (21) is disposed within the handle bars extending through partially or entirely along the length of the handle bar (10).

4) The handle bar arrangement of a bicycle as claimed in claim 3, wherein the outer contour of damping member (21) matches the inner contour of handle bar (10).

5) The handle bar arrangement of a bicycle as claimed in claims 3-4, wherein the damping member (21) is bonded within the handle bar with an adhesive.

6) The handle bar arrangement of a bicycle as claimed in claims 3-5, wherein the outer surface of the damping member (21) is not smooth but possesses uneven surfaces such as roughened or grooved.

7) The handle bar arrangement of a bicycle as claimed in claims 3-6, wherein the damping member (21) is of polymer such as polyurethane or viscoelastic polyurethane material or a silicon rubber insert with a modulus of elasticity sufficiently low, or a liquid such as SAE20 oil, water with sufficient bulk modulus to allow it to cause damping to absorb vibration from the road surface.

8) The handle bar arrangement of a bicycle as claimed in claims 3-7, wherein the shape of damping member (21) is annular, hexagonal mesh, reinforced hexagon, over expanded hexagon, square, flex core, double flex core or cross core.

9) The handle bar arrangement of a bicycle as claimed in claims 3-8, wherein the damping member (21) comprises of more than one layer of damping materials.
10) The handle bar arrangement of a bicycle as claimed in claims 3-9, wherein the damping member (21) insert includes a stopper at the extremity of the handle bar.