WO2016189554A2

WO2016189554A2 - Supportive motion assembly for bicycle drivetrain

Info

Publication number: WO2016189554A2
Application number: PCT/IN2016/050161
Authority: WO
Inventors: Dhananjay Vishnuprasad BHATT; Abdul Nanji MULTANI; Paragkumar Jyotishchandra TRIVEDI; Atulbhai Shantilal SHAH; Altaf Abdul MULTANI
Original assignee: Sardar Vallabhbhai National Institute of Technology
Priority date: 2015-05-27
Filing date: 2016-05-27
Publication date: 2016-12-01
Also published as: WO2016189554A3

Abstract

The present invention provides a supportive motion assembly, for bicycle driving system to convert passive reaction force of paddle action into active linear motion of bicycle, which comprises essentially of a disc plate, triangular brackets pair and compression springs. Incorporation of said motion assembly into drivetrain of conventional bicycle significantly 5 reduces the human efforts.

Description

SUPPORTIVE MOTION ASSEMBLY FOR BICYCLE DRIVETRAIN

Field of the Invention

The present invention relates to bicycle drivetrain systems and more specifically to a supportive motion assembly to convert passive reaction force generated during paddling operation into positive force for active linear motion of a bicycle.

Background of Invention

Bicycles probably are the foremost and lifelong type of manual power operated transportation vehicles developed by the human being, history of which may last to eighteenth century even.

The advent of modern materials and techniques has furthered the innovations in this field of bicycles. Major changes in bicycle form have often been initiated or accompanied by advances in drive-train systems and consequently, various specialized models of bicycles can be seen today.

However, one specific disadvantage live in with bicycles is that human efforts are needed in its running which makes driver's job difficult and sometime very unhealthy.

This difficulty is also due to the reason that reaction force generated during paddling operation of bicycle is left inefficiently utilized by existing drive mechanism of bicycles leading to require extra efforts from human to drive the bicycle to destination. This problem was seen addressed by providing the alternate mod of transport through motorbikes. However due to high cost, maintenance and non ecofriendly nature of motorbikes; same were not affordable as well as acceptable to many of people.

These disadvantages of motorbikes ensured that bicycle do not its attraction among people, even in the era of motorized vehicles.

Another reason for greater acceptance of bicycles by the people is that it is not just extraordinarily efficient in mechanical terms but also in biological terms. For example, the bicycle is the most efficient human-powered means of transportation in terms of energy a person must expend to travel a given distance and also, based on some estimates, that the carbon dioxide generated in the production and transportation of the food required by the bicyclist, per mile traveled, is less than 1/10 that generated by energy efficient motorcars.

Hence, bicycle was not just an efficient means of transportation, but an environment friendly means. Resultantly, from the beginning and still today, bicycles have been used by the people to serve their various needs such as; transportation, fitness training, recreational activities, traveling etc.

These advantages of bicycles along with the few disadvantages of motorbikes as mentioned above probably led people's focus back to bicycles, craze about which was increasing each day with increasing awareness of people.

Acknowledging the significance of same in public life; manufactures of bicycle have always strived to provide better and better solution in the form of improved driving mechanism for easy ride. Such solutions may include incorporation of various gear means for controlling and multiplying of force applied on paddles to drive the bicycle.

However it is pertinent to note here that said improvement came only with added purchase cost and complexity of drive means which takes such improved bicycles away from reach of common men. Thus it did not meet the actual demand of people getting improved driving mechanism for bicycles which are efficient as well as economic to be afforded by the people and capable to significantly reduce the human efforts required in driving of the bicycle.

Therefore, a need is always felt for modification over existing driving mechanism of conventional bicycle to provide improved driving mechanism for bicycle which are efficient and economic and can significantly reduce the human efforts.

Object of the Invention

Therefore the principal object of the present invention is to solve out the shortcomings of existing driving mechanism of conventional bicycle to reduce human efforts in driving of bicycle. Another object of the present invention is to suggest a solution for driving mechanism of conventional bicycle to trap the unutilized potential energy of paddle action force into useful positive energy of driving the bicycle, to reduce human efforts and save energy.

Another object of the present invention is to provide a modification over existing driving mechanism of conventional bicycle to trap the unutilized potential energy of paddle action force into useful positive energy of driving the bicycle, which could reduce human efforts and save energy.

Another object of the present invention is to provide a supportive motion assembly for existing driving mechanism which can trap the unutilized potential energy of paddle action force into useful positive energy of driving the bicycle, which reduces human efforts and save energy.

Another object of the present invention is to provide a supportive motion assembly for existing driving mechanism of conventional bicycle which is simple in design, lifelong, handy, inexpensive to manufacture, maintenance free, rugged in construction, easy to use, ecofiendly, efficient in operation, hence acceptable to larger public base.

Another object of the present invention is to provide an improved driving mechanism for bicycle which can provide smoother and comfortable ride giving users a feel of Gear cycle- without gears in cycle, with minimal addition of cost and complexity in driving mechanisms of bicycle.

Ultimate object of the present invention is to ensure an easier and comfortable ride in bicycles to promote public health and save environment.

For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be made to the accompanying drawings and descriptive matter which illustrates preferred embodiments of the invention.

Summary of Invention

In one aspect, the present invention provides a supportive motion assembly for bicycle driving system, to convert passive reaction force of paddle action into active linear motion of bicycle to smoother the ride and comfort thereof, which comprises essentially a set of disc plate, triangular brackets pair and compression springs.

In another aspect, said supportive motion assembly is installed between sprocket wheel and crank arm of bicycle crankset to utilize passive potential energy (reaction force generated in effect of paddle action) into useful positive energy of driving the bicycle.

In another aspect, the present invention proposes to use spring action to activate the idle reaction force of paddle action into useful positive energy for active linear motion o bicycle.

In other aspect, present invention provides a method for usage of supportive motion assembly for conversion of passive reaction force of cyclic motion into active linear motion, wherein passive reactive force generated during paddle action is activated through spring action to complement the cycle motion.

More aspects and embodiments of present invention would be apparent from following detailed description, appended claims and drawings attached.

Brief description of drawings

The various components of supportive motion assembly of present invention can be illustrated by following figures, wherein,

FIG. 01 -is a sectional view of conventional driving mechanism (chain and sprocket drive system) coupled with supportive motion assembly (disc plate + triangular bracket pair + compression springs) of present invention.

FIG. 02- shows the disc plate (to be securely mounted on sprocket wheel) of supportive motion assembly of present invention. FIG. 03 shows the right side crankarm (showing bottom axle and paddle axle joints) of supportive motion assembly of present invention.

FIG. 04- shows the Fixed-MS-Bracket- 1 (to be securely mounted on disc plate) of supportive motion assembly of present invention FIG. 05- shows the Movable-MS-bracket-2 (to be connected with bottom axle joint of crank arm in one side and freely mounted over corresponding Fixed MS bracket- 1 arms through compression spring on other side) of supportive motion assembly of present invention

FIG. 06 shows the compression spring (mounted between top ends of corresponding arms of movable MS bracket-2 and Fixed MS bracket- 1 which allows reciprocal movement of movable arms over fixed arms of bracket- 1 ) of supportive motion assembly of present invention

FIG. 07 is a perspective view to show adjustment of various components of assembly of present invention such as disc plate, fixed bracket, movable bracket and compression springs over driving sprocket of conventional bicycle. Detailed description of Invention

The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. The conventional drivetrain of bicycles generally includes a chain and sprocket assembly, which is also known as crankset or a chainset that converts the reciprocating motion of the rider's legs into rotational motion used to drive the chain, which in turn drives the rear wheel. It consists of one or more sprockets, also called chain wheels attached to the cranks, or crankarms to which the pedals attach. It is connected to the rider by the pedals, to the bicycle frame by the bottom bracket, and to the rear sprocket or freewheels via the chain. Thus, in conventional drivetrain, generally on right side of bicycle, at the ends of bottom axle, is fixed a crank-sprocket assembly and on the left side, only a crank, wherein said left and right crank or crankarms connects to pedals in their respective sides.

In existing driving mechanism of conventional bicycles, when force is applied on one of the paddle of bicycle, since both left and right cranks are 180 degree apart on either side of the bicycle, paddle rotates in downward direction of cyclic motion and thus energy applied on paddle is consumed in rotating the paddle which in turn to sprocket wheel. It' s only after that one side crank-paddle travels 180degree that other side crank-paddle comes in to action (e.g. if first left, then right, again left and then right like). Further, as we know that in existing paddling system; once force is applied on one of paddle to move crank in downward direction of cyclic motion, as per Newton 3rd law, a corresponding reaction force will be generated which will act on the other side paddle to move crank in upward direction by cyclic motion and therefore, rider will naturally reduces the force (or load) on other side paddle while moving in upward direction to maintain the speed harmony.

However at the same time we will notice that though reaction force generated due to action of one paddle helps in moving the other side crank-paddle up, it will have fluctuations in usage and action as it remains inefficiently utilised.

Therefore, the Inventors of this invention now suggest the supportive motion assembly for driving mechanism of convention bicycles which can be attached between sprocket wheel and crankarm of drivetrain to trap the unutilised potential energy (reaction force generated due to one side paddle action) into useful positive energy of moving up the paddle of other side and vice versa, which in turn to drives the sprocket wheel, which makes ride smoother and comfortable.

Refer now to FIG. 01 which gives a cross-sectional view of conventional chain and sprocket drive system coupled with supportive motion assembly of present invention.

Thus, in one of preferred embodiment, the present invention provides a supportive motion assembly, to complement the utilisation of reaction force so generated during the paddling operation in cyclic motion, which comprises primarily of; a disc plate [2], a triangular bracket pair [3A-B-C and 5A-B-C] and a compression springs [6A-6B-6C].

Accordingly, the Figures 02 to 06 shows cross-section views of various components of supportive motion assembly of present invention.

Refer now to Fig. 02 which is a cross-sectional view of a disc plate [2] of supportive motion assembly [2-6] of present invention.

Said disc plates [2] can be made of any metallic or non-metallic material which is durable and capable to sustain the load of bicycle. Inventors preferred Aluminium disc as same was lighter, durable and capable to handle the load also. Fig. 3 shows the crank arm generally used in bicycles which has top paddle axle joint (7 A) and lower bottom axle joint (7B).

Similarly, Figures 4 and 5, shows cross-section of triangular MS Brackets of fixed-type [3] and movable types [5]. Though in prototype prepared inventor have used specifically the triangular bracket [3A-B-C and 5A-B-C respectively] made of MS material; however constructing material and number of angles in a bracket (e.g. triangular, quadrilateral 3xN) should never be an issue, as long as material chosen is strong enough to sustain the action- reaction force or load and number of angle chosen in bracket allows to system work efficiently.

It is further shown that Fixed MS bracket [3] employs its arms/ blades/ projections [(as may be called as) which are of equal width, while in Movable brackets [5], the arms/ blades/projections tampering towards the top [5].

Thus, in one of another embodiment, motion assembly of present invention uses a fixed bracket with equal width arms [3A-B-C], and a movable bracket with arms tampering towards the top [5A-B-C]. Fig. 6 shows the cross-section of compression spring [6] used in motion assembly of present invention. This spring is preferably a heavy-duty helical spring designed for compression and tension.

In the present prototype; 3 springs [6A-B-C] have been used corresponding to triangular type fixed [3A-B-C] and movable brackets [5A-B-C] employed; and therefore number of such springs [6xN] may vary depending upon the number of arms used for fixed [3xN] and movable brackets [5xN] i.e. type of bracket such as triangular, quadrilateral.... as employed and the amount of force it needs to sustain. 3- Springs, [6A-B-C], are mounted between top end of respective arms on fixed MS bracket [3A-B-C]] and movable brackets [5A-B-C] to connect the adjacent arms of fixed and movable brackets. For example, an arm of fixed bracket [say 3A] connects to adjacent arm [say 5 A] of movable bracket through compression spring [say 6A] to make a pair of adjacent arm [3A+6A+5A]. Similarly other arms form two other pairs of it; 3B-6B-5B and 3C-6C- 5C ]. Where there are more than 3-such arms in a bracket [3xN and 5xN] ; number of arms pair can accordingly change to (3-6-5xN)

Thus in one of another embodiment of present invention; compression spring join the two arms of fixed and movable arm to form an arms pair wherein compression of said spring can allow reciprocal movement of movable bracket arm relative to fixed bracket arm to facilitate utilisation of reaction force into useful action of moving sprocket wheel which in turn to bicycle. In the present system, unlike in conventional drive system of bicycle wherein a sprocket wheel is directly connected with a crankarm; the sprocket wheel [1] is separated from the crank [7] through said supportive motion assembly [ 2- 6] placed between them.

Thus, in one of another preferred embodiment, the present invention provides a supportive motion assembly which is supposed to be positioned between the sprocket wheel [1] and Crankarm [7] of existing chain and sprocket drive mechanism of bicycle.

Therefore generally to install the supportive motion assembly of present invention into drivetrain of bicycle, the sprocket and crank of the conventional system can be little modified, as per the requirement.

First a disc plate [2] is arranged on crank side chain sprocket [1], then a Fixed MS bracket- 1 [3] is placed over said plate and then both are coupled with sprocket wheel through nut and bolt [4], alternatively can be welded, as suitable.

Said disc plate [2] is mounted on sprocket wheel [1] keeping in a sufficient space for smooth movement of chain over said sprocket. Thus, in present system, disc plate [2] can act as chain cover as well as a platform for holding the motion assembly of present invention. Similarly, a Movable MS bracket-2 [5] is fixed or welded with axle end of crankarm [7B] and then the composite [5 + 7] form is fitted on said Fixed MS bracket- 1 [3] through bottom axle fitting. The compression springs [6A-B-C] of diameter'd' is mounted between top ends of corresponding projections of Fixed bracket- 1 [right angle projections 3A-B-C] and Movable bracket-2 [projections 5A-B-C] brackets respectively, with the help of bolt and nuts including locknut [4a-b-c...] and a spacer (washer), to allow reciprocal movement of movable arms of MS bracket-1 [5A-B-C] relative to fixed arms of MS bracket- 1 [3 A-B-C] in effect of compression of spring due to paddle action force.

Thus, the whole assembly can be divided into two-segment based on relative attachment and position of various components of present motion assembly over bottom axle of bicycle drivetrain.

Inner side segment include; chain sprocket [1] + aluminium disc [2] + Fixed MS bracket-1 [3], which is positioned inside the paddle axle end and, Outer side segment which includes; a crank [7] + Movable MS bracket-2 [5 A-B-C] + compression springs [6A-B-C], a composite which is positioned over said fixed bracket [3].

Thus, combination of said inner side and outer side segments makes the supportive motion assembly of present invention.

In functioning; the present invention follows the scientific principle that when force is applied on wheel through paddle movement, equal force arise all around the circumference of wheel and due to this equality that, this force remains passive. Through present invention this force is activated by making it unequal using activation means such as spring action.

Therefore it is this idle force that inventor of present invention proposes to use as an additional positive energy for driving of the bicycle, to make drive smoother and comfortable. In working of system- When peddle force is applied on sprocket wheel side, as in normal paddling system, the 120 degree apart freely mounted springs will be compressed in motion direction and once the minimum balancing speed is achieved, the spring movement will add the ΔΧ force in motion direction to complement the driving force for bicycle. To understand it further- when a paddle is actuated, it activates the triangular arms of movable bracket which then compresses the compression spring relative to corresponding arms of fixed arms to provide an additional driving force to sprocket wheel which runs the bicycle to make ride smoother and comfortable.

Thus, present invention enables to use passive reaction force generated during action of one of paddle in moving up the other side paddle and vice versa, so as to utilise said idle force into positive force for driving the sprocket wheel which in turn to bicycle. Cyclists have given tremendous positive response to improved driving mechanism in conventional bicycle by present invention and, though it would make complex for force- analysis theory application, a thumb rule calculation is that it reduced almost 50% of human efforts to make ride smoother and comfortable for users. Therefore now we understand that supportive motion assembly when coupled with conventional driving mechanism had significantly improved the driving mechanism of conventional bicycle to give a joy of "gear cycle- without gear".

It provided an improved bicycle drive system which is energy saving, maintenance free and incurs a minor cost addition to remain readily affordable by people, ensuring optimum utilisation of technology for the benefit of people.

Though the present invention is exemplified with improving drive mechanism of bicycle only, same could be equally applicable to all those vehicles or system using human efforts or machine automation wherein rotary/cyclic motions are converted into linear/rotational motion thereof. With little modification to such existing systems, the present invention could be installed in them to aid the driving of such systems/vehicles which could significantly reduce the human/machine efforts. Thus present invention could be useful for most of the transportation system on road/rail and also on or under water/air which follows similar drive mechanisms.

The Non-limiting examples can include bicycle, tricycle, hand rickshaw, hand lorry, camel/ bullock/ horse cart, lake/river boat; peddle power generators and single wheel cycle normally used in sports/circus and like others which follows similar power transmission mechanism for moving, could be of specific mentioning wherein present invention could work wonder and therefore may need immediate application of present invention to reduce the burden of drivers. Alternatively, it should be possible to use the technology with mechanised motorised auto system used in passenger/goods transport systems.

Thus, without limiting to modification of drive mechanism of just bicycles, present invention should mean to protect the basic idea of using motion assembly of present invention in supporting the existing drive mechanism to convert the passive reaction force generated during paddling/rotary motion into useful positive energy as an additional force to drive the system which can reduce the human/machine efforts required and therefore same needs to be understood in its actual sense rather than limiting to one drive system of bicycle.

Claims

1) A supportive motion assembly for bicycle driving system to convert passive reaction force of paddle action into active linear motion of bicycle, which comprises essentially of a disc plate, brackets pair and compression springs.

2) The assembly as claimed in claim 1, wherein said disc plate is securely mounted on a driving sprocket.

3) The assembly as claimed in claim 1, wherein said brackets includes essentially atleast; a fixed bracket and a movable bracket.

4) The assembly as claimed in claim 3, wherein said brackets are preferably triangular in shape.

5) The assembly as claimed in claim 4, wherein said fixed bracket preferably has equal width arms while movable bracket arms tapering towards the top.

6) The assembly as claimed in claim 3, wherein said fixed bracket is securely mounted on disc plate.

7) The assembly as claimed in claim 3, wherein said movable bracket is securely connected to crankarm.

8) The assembly as claimed in claims 3 through 7, wherein said movable bracket is freely mounted over fixed bracket to form a bracket pair.

9) The assembly as claimed in claim 8, wherein adjacent arms of said fixed and movable arms connects through compression springs to form arms pair which allows reciprocal movement of said movable arms relative to fixed arms.

10) A method for usage of supportive motion assembly for conversion of passive reaction force of cyclic motion into active linear motion, wherein passive reactive force generated during paddle action is activated through spring action to complement the cycle motion. 11) An assembly and method as claimed in preceding claims which applies equally in transmission mechanism involving conversion of cyclic motion into linear motion employing human efforts or machine automation.