WO2023180928A1

WO2023180928A1 - Electric powertrain for automotive and other applications

Info

Publication number: WO2023180928A1
Application number: PCT/IB2023/052765
Authority: WO
Inventors: Gursaurabh SINGH
Original assignee: Singh Gursaurabh
Priority date: 2022-03-21
Filing date: 2023-03-21
Publication date: 2023-09-28

Abstract

A robust electric powertrain is disclosed herein, which is particularly in the form of a sprocket-engaging mid-drive arrangement comprising of an electric motor, an on-board battery, gearing, a free-wheeling front sprocket, a motor controller, circuitry for charging, discharging and signal conditioning, an auxiliary power circuit (for powering appliances such as cell phone / lamp etc.), and a housing to contain the above-listed components in a minimal spatial envelope. Said robust electric powertrain is capable of fitment to Cycles, therein capable of being charged to thus serve as a powertrain optionally for propulsion of said bicycle in particular or furthermore or optionally for running of non-automotive applications.

Description

BEFORE THE INTERNATIONAL BUREAU OF THE WORLD INTELLECTUAL PROPERTY ORGANIZATION

NON PROVISIONAL APPLICATION FOR PATENT

PCT Rule 19.1 (a)(iii)

Title : Electric powertrain for automotive and other applications

Applicant : Gursaurabh Singh

75, MBK, Sector 13, Dwarka, New Delhi, Delhi, India - 110078

Priority : IN202211015376 filed on 21/03/2022

Inventor : Gursaurabh Singh

75, MBK, Sector 13, Dwarka, New Delhi, Delhi, India - 110078

Attorney file ref. : IR6945

Address for Rohit Nitin Deshpande service : (Advocate & IP Attorney)

Inventillect Consultants, Office No. 307, Business Guild Condominium, Apex Colony, ILS Law College Road, Erandwane, Pune, Maharashtra, India - 411004

Complete Specification

“Electric powertrain for automotive and other applications”

Cross references to related applications: This complete specification is filed further to application for patent No. 20221 1015376 filed on 21/03/2022 with provisional specification, the contents of which are incorporated herein in their entirety by reference.

Field of the invention

This invention is related generally to the field of Prime Movers. More particularly, the present invention outlines the construction, implementation, and operations of an electric device which finds applicability as a powertrain, primarily for assisting in propulsion of human-powered vehicles, and secondarily for running non-automotive loads such as those for lighting, refrigeration and so on.

Definitions and interpretations

Before undertaking the detailed description of the invention below, it may be advantageous to set forth definitions of certain words or phrases used throughout this patent document: the terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation; the term “or” is inclusive, meaning and/or; the phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect, with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like, and the following terms shall have their underlying meanings-

“Prime Mover” shall refer a machine that converts one or more forms of energy (chemical, electrical, fluid pressure/flow, etc.) into mechanical force;

“Cycle” shall refer and include bicycles, tricycles, quadracycles, unicycles, or other human-powered vehicles from one or more rider/s (single rider, tandem / pedibus etc.) to one or more drive wheel/s, further including those with mechanisms (such as gears etc.) to convert speed and torque.

“MID” shall refer to a Multi Information Display. Background of the invention and description of related art

Power collection, transmission, and conversion in relation to a human-centric utility are topics of critical attention in all walks of engineering. In fact, the developments in this discipline have been majorly instrumental in bringing about the era of industrialization and modernization seen in the past few decades. Today, these topics continue to be very important for research and developmental activities being undertaken globally, with the added acute wants of sustainability and minimal environmental impact.

Development or augmentation of powertrains in vehicles / machines has been a popular focus of research wherein the need for obviating fossil-based polluting fuels has been recognized as one of the prime keys for achieving the acute wants voiced in the preceding paragraph.

Coming to the locus of this invention, the reader shall generally note that a drivetrain of a conventional Cycle is a simple mechanical construct which sources power from a reciprocating motion (such as pedaling) performed by a human rider. The power so sourced is used to rotate the drive wheel of said Cycle, to thus propel the Cycle and effect locomotion.

Various arrangements are known to constitute the drivetrains of Cycles, including those which are actuated by the rider’s legs or otherwise by the rider’s hands (handcycle), body motion (rowing / hand and foot, Excycle etc.). These generally subscribe to a generic model of using a crankset, chain, groupset / gruppo and pedals. However, since all of these, without exception, squarely depend on endurance of the rider, find very limited applicability in terms of travel range, speed, load / carriage ability and thus often not the choice of transport, despite being cost-effective, healthy for the rider as well as non-polluting, non-impacting and sustainable for the environment.

Prior art bears references of attempts to the aforementioned limited applicability of Cycles, by introducing electric motors to drive the conventional bicycle transmissions. While there were many common art references researched by the inventor(s) in ensuring that the present invention is novel, the following patent prior art was identified as related to the present invention, and thus worthwhile to discuss in more detail in context of the present invention. One example is US10315726 (2016; Issued to Britt Jackson, shown in FIG. 1 ) teaches a mid-drive arrangement for electric bicycles. Another example is JP2002284085A (2002; Issued to Honda Motor Co Ltd, shown in FIG. 2) which teaches a motor-assisted bicycle in which a motor is associated with a crank pedal having a rear wheel that is driven by a human to perform a rotational operation.

Prior art however, to the limited extent presently surveyed, does not list a single effective solution embracing all considerations mentioned hereinabove, among which the following major aspects remain unaddressed- a) Undue complexities in motors and their assemblies which require repeated precise alignments; b) High costs of manufacturing, sourcing, fitment, and operations of electric kits available for Cycles; c) High bulk, non-compact packaging, weight of electric conversion kits; d) Difficulties in retro-fitment to conventional Cycles having sprocket-chain based drivetrains; e) Non-reversion of Cycles to be used in traditional manner (human pedaling power) after conversion to electric operability; f) Limited travel range, speed, load / carriage ability after conversion of Cycles to electric operability; g) Over-reliance on presence of charging infrastructure; h) Non-organized packaging of ancillaries, including battery, electric transmission components etc. which besides requiring separate provisioning of mooting, also malign design aesthetics of the final product;

I) Virtual non-use for any other application, once a electric motor assembly is fitted onto a Cycle; j) Limited endurance to wear and tear, environmental exposure (temperature, moisture etc.), dust etc.; k) Limited protection against hazards due to fire, water logging etc.

Due to the above lacunae, an acute necessity-to-invent is preserved, which is actioned by the applicant named herein who, as result of his focused research, has come up with novel solutions for resolving said shortcomings of art once and for all. Work of the presently named inventor, specifically directed against the technical problems recited hereinabove and currently part of the public domain including earlier publications and posts, is neither expressly nor impliedly admitted as prior art against the present disclosures. A better understanding of the objects, advantages, features, properties and relationships of the present invention will be obtained from the following detailed description which sets forth an illustrative yet-preferred embodiment.

Objectives of the present invention

The present invention is identified in addressing at least all major deficiencies of art discussed in the foregoing section by effectively addressing the objectives stated under, of which:

It is a primary objective of the present invention to establish a powertrain particularly in the form of a portable sprocket-engagingmid-drive arrangement which is capable of serving as a powertrain in the propulsion of human powered vehicles, Cycles in particular as well as running non-automotive applications.

It is another objective hereof, further to the aforesaid objective(s), that the powertrain so proposed is capable of easily-releasable engagement with Cycles with minimal tooling.

It is another objective hereof, further to the aforesaid objective(s), that the powertrain so proposed is capable of being charged from the conventional human-powered propulsion of the Cycle and conversely utilizing the charge generated to propel said Cycle in an assistive or fully automatic mode.

It is another objective hereof, further to the aforesaid objective(s), that the powertrain so proposed is capable of plug-and-play utility with conventional Cycles as part of either between retrofit as well as new production arrangements.

It is another objective hereof, further to the aforesaid objective(s), that after fitment of the powertrain to a Cycle, said Cycle is still operable conventionally via human pedalling.

It is another objective hereof, further to the aforesaid objective(s), that the powertrain so proposed has high endurance to wear and tear, environmental exposure, as well as fire / water logging / dust / mud hazards.

It is another objective hereof, further to the aforesaid objective(s), that the powertrain so proposed is not riddled with technical complexities and / or high costs.

It is another objective hereof, further to the aforesaid objective(s), that fitment of the powertrain so proposed to a Cycle implies none, or minimal if at all, changes in the manner in which the human user is to operate said Cycle.

The manner in which the above objectives are achieved, together with other objects and advantages which will become subsequently apparent, reside in the detailed description set forth below in reference to the accompanying drawings and furthermore specifically outlined in the independent claims. Other advantageous embodiments of the invention are specified in the dependent claims.

Brief description of drawings

The present invention is explained herein under with reference to the following drawings, in which:

FIG. 1 is a representative drawing of a prior art invention.

FIG. 2 is a representative drawing of another prior art invention.

FIG. 3 is a photograph showcasing one view of the present invention being outfitted to a conventional bicycle.

FIG. 4 is a photograph showcasing the setup of FIG. 3, with sprocket-engaging means visible.

FIG. 5 is a photograph showcasing the setup of FIG. 3 as seen from the other side of the bicycle.

FIG. 6 is a schematic drawing of the unibody electric powertrain hereof, showing in a perspective view, few components in exploded format to illustrate the manner of assembly onto a bicycle.

FIG. 7 is another schematic drawing of the unibody electric powertrain hereof, showing a sprocket-side view of said powertrain.

FIG. 8 is another schematic drawing of the unibody electric powertrain hereof, showing the opposite side as that shown in FIG. 7.

FIG. 9 is an isolated drawing of the electric motor with associated controller as per the present invention.

FIG. 10 showcases the peripherals to be assembled with the unibody electric powertrain of the present invention, particularly being (A) a throttle unit having an MID and lock; (B) Sprocket; (C) Set of affixing clamps; (D) Chain cover; (E) set of bolts; (F) sprocket-side pedal; and (G) Axle.

FIG. 11 showcases the axle of FIG.10G, particularly being (A) central shaft; (B) screw cap; and (C) rotatable bearing.

The above drawings are illustrative of particular examples of the present invention but are not intended to limit the scope thereof. The drawings are not to scale (unless so stated) and are intended for use solely in conjunction with their explanations in the following detailed description. In above drawings, wherever possible, the same references and symbols have been used throughout to refer to the same or similar parts. Though numbering has been introduced to demarcate reference to specific components in relation to such references being made in different sections of this specification, all components are not shown or numbered in each drawing to avoid obscuring the invention proposed.

Attention of the reader is now requested to the detailed description to follow which narrates a preferred embodiment of the present invention and such other ways in which principles of the invention may be employed without parting from the essence of the invention claimed herein.

Detailed description

Principally, general purpose of the present invention is to assess disabilities and shortcomings inherent to known systems comprising state of the art and develop new systems incorporating all available advantages of known art and none of its disadvantages, to thereby establish an electric powertrain for automotive and other applications.

Before laying out the present invention in detail, it shall be worthwhile to note that the use of hub motors and friction rollers for contacting the drive / driven wheels has given precedence to mid-drive systems due to inherent stability, weight-distribution, serviceability and other advantages. The present invention is an significant advancement in this line as particularly set forth in the continuing portion of this disclosure.

Preliminarily as shown in the accompanying FIG. 3 and FIG. 4, the disclosures herein are directed to a sprocket-engaging mid-drive system for fitment in relation to a conventional Cycle for conversion of said conventional Cycle to an electric Cycle. With specific reference to the accompanying FIG. 3, FIG. 4 and FIG. 5, it can be seen that the sprocket-engaging mid-drive system comprises an electric motor, an on-board rechargeable battery, gearing, a free-wheeling front sprocket, a motor controller, circuitry for charging, discharging and signal conditioning, an auxiliary power circuit (for powering appliances such as cell phone / lamp etc.), and an all-weather housing to contain the above-listed components in a minimal spatial envelope, and shield them from the elements and thereby enable high endurance to wear and tear, environmental exposure, as well as fire / water logging / dust / mud hazards. According to a related aspect, the sprocket-engaging mid-drive system includes gearing suitable to the end-application. For example, gearing (or any off-shelf gearbox) are included when the end-application is locomotion biased, for example driving a bicycle wherein the requirement is primarily for end-speed and not as much as torque. However conversely, suitable gearing (or any off-shelf gearbox) are included when the end-application depends on availability of high torque, for example where the load is a sugarcane crushing machine, or grass cutting machine etc.

According to a related aspect, the sprocket-engaging mid-drive system is connected, via suitable cabling to an accelerator handle fitted onto the handle grip of the Cycle. Said handle unit also houses an Ignition switch, by which the user may select actuation of the sprocket-engaging mid-drive system to an ON state. And by turning said accelerator handle grip, the user can control the actuation and speed by which the system can propel the Cycle.

According to another related aspect, the sprocket-engaging mid-drive system is connected, via suitable cabling to a display unit mounted onto the handle of the Cycle for easy visibility to the rider of said Cycle. This display unit consists of an electronic / analogue / mixed-type unit, with lamps / markings to denote information including state of charging, power mode etc. in relation to said system.

According to another related aspect, the sprocket-engaging mid-drive system is housed inside an all-weather housing which is contoured and dimensioned for universal fitment within the main frame of Cycles as will be disclosed later in this document, therein allowing a one-size / configuration fits all advantage.

With specific reference to the accompanying FIG. 4, it can be seen that the sprocketengaging mid-drive system is intended for fitment using basic tools (spanners, screw drivers and the like) within the main frame of a Cycle, within the triangular area formed by the down tube, seat tube and the top tube of said Cycle, particularly near to the lower bracket shell as shown in FIG. 3 and FIG. 5. The reader shall appreciate that once fitted in to this position, the sprocket-engaging mid-drive system engages with the chain ring / sprocket as shown in FIG. 4. As will be evident to the reader from the foregoing disclosures, the electric powertrain proposed herein is non-dependent on spoked wheels, or replacement of spokes for accommodation of hub motors.

Reference is now made in further detail, as to the construction of the heart of this invention, that is the portable sprocket-engaging mid-drive system hereof and the peripherals / ancillaries that accompany the same for implementation of the present invention.

Referring to the accompanying FIG. 6 and FIG. 7 generally, it can be seen that, three dimensionally, the housing (601 ) is substantively triangular in shape bounded by three substantively flat sides (602, 603, and 604) which is closed by two opposing faces (605 and 606). Referring back to the FIG. 3 and FIG. 4, it can be appreciated that when the portable sprocket-engaging mid-drive system hereof is fitted to a bicycle, the sides (602 and 604, highlighted by dotted lines) are positioned parallel / flush to the down tube and seat tube respectively of the bicycle. Apertures (701 , 702, 703 and 704) are machined to traverse the face (605) for correspondingly allowing the four bolts (1005, 1006 and two more not shown in the drawings but to be visualized in analogy) to pass through and engage with the bolt-wells (1011 , 1012 and two more not shown in the drawings but to be visualized in analogy) in the clamps fixed onto the downtube and seat tube of the Cycle, to thus allow the portable sprocket-engaging mid-drive system hereof to be locked into position for implementation of the present invention as will be disclosed in detail in the disclosures to follow hereunder.

According to a related aspect, the apertures (701 , 702, 703 and 704) are not circular, but oval in shape, for allowing a restricted freedom of movement / translation of the four bolts (1005, 1006 and two more not shown in the drawings but to be visualized in analogy) in order to allow the portable sprocket-engaging mid-drive system hereof to be locked into position at a best suitable position.

According to another related aspect, the housing (601 ) is made by aluminum casting (unibody) or each part casted separately using appropriate molds. Alternatively, the housing (601) is made of suitable resilient and workable material such as steel, carbon fiber etc. As can be seen further in FIG. 6, a handle (607) is welded to or cast in-situ with the top flat side (603) for allowing a user to lift up / place down and otherwise carry the portable sprocket-engaging mid-drive system hereof.

As can be seen further in FIG. 6, two ports (608 and 609) are provided traversing the face (605). These ports (608 and 609) are cylindrical in cross-section with threaded mouths which can be reversibly closed / opened with help of screw-on lids (610 and 611). The port (608) is for allowing the user to connect a utility power cable for charging the battery of the portable sprocket-engaging mid-drive system hereof, to thus allow charging in an independent manner. The port (609) is for allowing the user to connect a power cable for leading out to an electrical load, such as a mobile phone / bulb etc., which can be powered thus by electrical charge stored in the battery of the portable sprocket-engaging mid-drive system hereof. It shall be understood that the functionality of ports (608 and 609) is interchangeable, with either capable of being wired and thus repurposed for the other as per choice of the user.

As can be seen further in FIG. 4 and FIG. 6, the face (605) is provisioned with another traversing port (613) through which the shaft of the electric motor (802, seen in FIG.8) (or auxiliary shaft if connected to a non-axial gear box) is coaxially protruded to receive a motorized toothed cog / gear (614). Ratio of the diameter of said gear (614) to that of the sprocket (615) is of ratio selected between 1 :1 to 1 :50 as per speed or torque priority of the application intended. Said gear (614) engages with the chain (401 ) of the bicycle at a position overhead the sprocket (615) of said bicycle, when the portable sprocket-engaging mid-drive system hereof is positioned at the base of the triangular area formed by the down tube (402), seat tube (403) and the top tube (404) of the bicycle.

As per a related aspect hereof, length of the replacement chain (401) needs to be increased to accommodate / loop around both the gear (614) and sprocket (615). An increase of 5% to 30% is required depending on the Cycle used, with around 10% increase for bicycles and more up to 30% for tricycles / cycle-rickshaws and so on. A longer chain is provided along as an ancillary for conversion of a conventional Cycle to one outfitted with the powertrain of the present invention.

As per another related aspect hereof, in a further embodiment (not shown in the drawings), the chain (401) is intended to be outfitted with a conventional tensioner, which maintains said chain (401) in required tension in position, and disallowing it to slip out of position / alignment required for driving the Cycle as per implementation of the present invention.

The reader shall appreciate now, that once the sprocket-engaging mid-drive system is engaged with the chain ring / sprocket as mentioned above, the Cycle is still usable as before, that is, powered via pedaling by the rider, while being completely converted for electric-powered operation when desired by the rider. Hence, a bicycle outfitted with the present invention is enabled to selectively operate alternatively, at discretion of the user by actuation of a switch, in three distinct locomotion modes as shown in Table 1 below.

Table 1

It shall be generally understood that the ratio of diameters of the cog (614) and the sprocket of the bicycle and frequency of teeth therein are stochastically related, analogous to gearing ratios, to thus decide pedaling power to charging throughput of the portable sprocket-engaging mid-drive system hereof. It is intended herein to include all iterations of the ratios / tooth densities in different embodiments of the present invention.

Internal assembly / packaging of components of the portable sprocket-engaging middrive system hereof can be seen in FIG. 8. As seen here, a battery (801) is connected to a controller circuit (803) and said controller circuit (803) is connected to an electric motor (802), to thus allow the controller circuit (803) to regulate power supply to the electric motor (802) as per throttle input received from the throttle unit as will be disclosed later in this document. The components (801, 802 and 803) are anchored, via screw bolts / riveting internally to sides (603, 602) and face (605) respectively. Suitable electrically conductive wiring / data cabling is provisioned to interface these components for actuation in response to a throttle unit to be explained later in this document. In a related aspect seen particularly in FIG. 8, it shall be appreciated that the face (606) is independently screwed onto the lateral sides of the triangular box formed by sides (602, 603, and 604) to allow easy access for repair / servicing / replacement of components inside the portable sprocket-engaging mid-drive system hereof.

FIG. 9 is an isolated drawing of the electric motor with associated controller circuit as per the present invention. To note, the controller circuit has three leads and corresponding sockets for interfacing between the rechargeable battery (801) and the electric motor (802), to thus regulate the power supply from the battery (801 ) to the electric motor (802) as per throttle input received from the throttle unit via corresponding wiring from the throttle unit. The leads and connectors are for conventional purposes, such as lock, throttle input, brake lights etc.

As can be appreciated by the reader, when the user opens up the throttle, more power is fed correspondingly from the battery (801) to the electric motor (802) to thus cause the electric motor (802) to rotate faster, thereby delivering more power to the driving wheel of the Cycle for acceleration / increased traveling speed. Conversely, when the user closes / shuts down the throttle, power feed from the battery (801) is correspondingly lessened / cut to the electric motor (802) to thus cause the electric motor (802) to rotate slower / stop, thereby delivering lesser / no power to the driving wheel of the Cycle for deceleration / returning the Cycle into a free-wheeling mode or manual (pedaling) mode again.

As mentioned before in this document, the sprocket-engaging mid-drive system hereof includes gearing (901 ) suitable to the end-application. For example, gearing (or any off-shelf gearbox) are included when the end-application is locomotion biased, for example driving a bicycle wherein the requirement is primarily for end-speed and not as much as torque. However conversely, suitable gearing (or any off-shelf gearbox) are included when the end-application depends on availability of high torque, for example where the load is a sugarcane crushing machine, or grass cutting machine etc.

Implementation of the present invention is intended as a electric conversion kit for a bicycle. In line, FIG. 10 showcases the peripherals to be assembled with the unibody electric powertrain of the present invention. FIG.10A shows a throttle unit having an MID and lock. This is the human-machine interface of the present invention, for fitment at position of the handle-grip of said bicycle for allowing the user to lock, actuate and control the performance of the sprocket-engaging mid-drive electric powertrain. This unit is connected to one end of the handlebar of the Cycle. Turning the throttle (1001) signals the electric motor to rotate faster, hence accelerating the Cycle. Correspondingly, the MID (1002) displays relevant information including battery status, speed, time, distance travelled etc. The key lock (1003) allows the user to switch the portable electric powertrain of the present invention between its ON and OFF states. Appropriate cabling (1004) is provided leading out from the throttle unit to connect with the corresponding connectors of the controller circuit.

FIG.10B shows the sprocket of the Cycle with which the chain of said Cycle is interfaced / looped as shown in FIG. 4. Toothing, design etc of this sprocket is as per standard practices in the industry for said sprockets.

FIG.10C shows the set of substantially elongated clamps used to fix the portable electric powertrain of the present invention in position when the portable sprocketengaging mid-drive system hereof is positioned at the base of the triangular area formed by the down tube, seat tube and the top tube of the bicycle. Position of one of said clamps can be seen in FIG. 5. Each of said clamps consists of two mated contoured portions (1007 and 1008) which, when facing each other, circumscribe a continuous cavity for snugly encircling the seat tube or down tube of the Cycle. Two larger apertures

According to a related aspect herein, it shall be understood that the cross-section of said continuous cavity can be designed as per the cross-section of the downtube and seat tube of the Cycle to be fitted to, or else, gaskets of suitable material / compressible material / shape-compensating / shape-memory material may be used, as common to art, for snugly encircling the seat tube or down tube of the Cycle.

As seen in FIG. 10C, the two mated portions of said clamps are bolted together using six bolts (shown for understanding by common numeral 1009). The bolts are driven through apertures in one portion (1007) into tapped / internally-threaded bolt-wells (shown for understanding by common numeral 1010) machined / cast in-situ into the other portion of said clamps, whereupon the bolts may be screwed in tight with help of a screw-driver / Allen key / wrench etc. depending on design of the head of said bolts. Accordingly as seen in FIG.6, the set of clamps are positioned on the seat tube and down tube of the Cycle so as to flush fit onto the underbelly of face (605) of the portable electric powertrain of the present invention, and fixed into position via four screw bolts (two bolts, 1005 and 1006, shown separately in FIG.10E, rest of the bolts can be visualized in analogy) which traverse through corresponding oval apertures (701 , 702, 703 and 704 shown in FIG. 7) provided the body of the face (605), into tapped / internally-threaded bolt-wells (1011 and 1012, shown separately in FIG.10C, rest of the bolt-wells in the other clamp can be visualized in analogy).

FIG.10D shows a chain cover (1007) to be fitted onto the chain of the Cycle when the chain is fitted over the gear (614). Fitment of the cover (1007) can be visualized in FIG. 3 and FIG. 12, wherein it can be seen that advantageously, as a partial cover, the chain cover (1007) need not be removed once bolted in position onto the face (605) if chain has to be fixed / removed for servicing / replacement.

It shall be appreciated by the reader that the cog (614) and sprocket of the Cycle are coplanar. However, fitment of the cover (1007) is not co-planar and hence expected to introduce an offset which may interfere with the sweep of the sprocket-side pedal of the Cycle. In the event this happens, the applicant herein proposes to address this issue with a replacement custom designed pedal (1008) seen in FIG.10F. As seen here, the shaft of said pedal (1008) bears a convexity / bend to accommodate the aforesaid offset, as can be visualized in FIG. 3. Left side replacement pedal is also provided to the user, however more as an aesthetic match to the custom designed pedal (1008).

To note, upon fitment of the electric powertrain and ancillaries proposed herein, it is intended that said Cycle yet retains being usable in either free-wheeling mode or manual (pedaling) mode, and importantly, that the user need not pedal the Cycle when run in fully electric mode. To achieve this, a special replacement axle is provided as shown in FIG. 10G, the components of which are shown further in FIG. 11 (A to C). FIG. 11 showcases the axle of FIG.10G, particularly being (A) central shaft; (B) screw cap; and (C) rotatable bearing, which axle is to be used in place of the regular axle of the Cycle. The axle shown in FIG.10G comprises a central shaft for rotation, a screwcap and freely rotatable bearing, which arrangement allows it to fit into the existing axle hub of the Cycle and makes it possible for the user to either pedal the cycle conventionally when in fully manual mode, pedal the cycle with less effort in the electric assist mode, and otherwise use the pedals as stationary footrests (alike a motorized two wheeler) when running the Cycle in fully electric mode, that is, when propelled by the powertrain of this invention or while free-wheeling the bicycle during manual pedalling by the user.

As will be evident to the reader hereof, the electric powertrain proposed herein is usable in a stationary mode, being a generator mode, besides the three distinct locomotion modes mentioned above. Here, the bicycle is kept stationary on its stand, and pedalled in position by the user, to thereby convert mechanical force applied into electricity which can be stored in the battery on-board the sprocket-engaging mid-drive system or alternatively supplied in real time, via suitable signal conditioning means, to an electrical load. Hence, the present invention is totally free from any charging infrastructure dependency.

According to another aspect hereof, the battery of the electric powertrain proposed herein can be charged consequent to pedaling by the user either while the bicycle is standstill (on its parking stand) or else in motion (driven by the user) or via direct feed from a utility power source.

Reduction to practice

The present invention has been reduced to practice by the Applicant named herein. In an isolated embodiment, the electric powertrain proposed herein, with its ancillaries, together provided as an electric conversion kit, is fitted (either as original fitment at the time of production of bicycles or retrofitting to existing bicycles) to a conventional bicycle, while using basic tooling (such as spanners / screw drivers / Allen keys) via the following steps- a) Removal of original chain of the bicycle b) Removal of original pedals of the bicycle c) Removal of original axle of the bicycle d) Removal of right-side handle grip of the bicycle e) Fitment of the throttle unit provided in the kit in place of the removed handle-grip. f) Fitment of the new axle and sprocket provided in the kit into the axle hub of the bicycle g) Fitment of the new pedals provided in the kit at ends of the new axle h) Fitment of the clamps in approximate position on the downtube and seat tube i) Placing the powertrain into position within the triangular area formed by the down tube, seat tube and the top tube j) Looping the new chain provided in the kit over the sprocket and gear of the powertrain, ensuring a correct fit with sufficient tension in the chain. k) Securing the powertrain into position by tightening the bolts into the clamps. l) Connecting the electrical circuit / connectors of the throttle unit and the powertrain.

Though the components therein are capable of variations to suit end applications / performance, an exemplary building list of materials is provided herein in Table 2 for sake of non-limiting / non-restrictive reference-

Table 2

Claims

According to another aspect hereof, the electric powertrain proposed herein is also intended for being used, as-is or with minimal localizations if at all, for non-automotive applications which typically require a rotational motion for performance. Examples of such application including compressors of refrigerators, electricity generators, fans, ventilation equipment, exhaust equipment, flour mills, rotary cutters, grass mowers, small agrarian tools, stand-alone generators and their equivalents.

From the foregoing narration, an able electric powertrain for automotive and other applications is thus provided with marked novelty, inventive contribution, and industrial applicability than any background and / or prior art. As will be realized further, the present invention is capable of various other embodiments and that its several components and related details are capable of various alterations, all without departing from the basic concept of the present invention. Accordingly, the foregoing description will be regarded as illustrative in nature and not as restrictive in any form whatsoever. Modifications and variations of the system and apparatus described herein will be obvious to those skilled in the art. Such modifications and variations are intended to come within ambit of the present invention, which is limited only by the appended claims.

Claims

I claim,

1] An electric conversion kit for a bicycle, said kit comprising- a) A sprocket-engaging unibody mid-drive electric powertrain, having a motorized gear in particular, and suitable apertures on one of its faces for being positioned, via bolting, within the triangular area formed by the down tube, seat tube and the top tube of the bicycle to thereby propel said bicycle at instance of the user; b) A human-machine interface for fitment at position of the handle-grip of said bicycle for allowing the user to lock, actuate and control the performance of the sprocket-engaging mid-drive electric powertrain; c) A set of two substantially elongated clamps, with each having a hollow lumen along their long axis for being releasably fixed around the downtube and seat tube of the bicycle respectively to thereby serve, via bolt-wells in their backs, for anchorage of two bolts per clamp, with each bolt traversing a face of the sprocket-engaging mid-drive electric powertrain to securely hold said sprocket-engaging mid-drive electric powertrain in position; d) A replacement axle, of length 7.25 inches in particular, for substituting the original axle of the bicycle, for allowing the pedals to be static while the bicycle is being propelled by the sprocket-engaging mid-drive electric powertrain; e) A substantially elongated replacement chain for substituting the original chain of the bicycle, for allowing a length sufficient to loop around the rear sprocket, front sprocket and the motorized gear of the sprocketengaging mid-drive electric powertrain; f) A couple of replacement pedals for substituting the original pedals of the bicycle, wherein one pedal has its shaft contoured to accommodate the offset presented by the plane defined by the replacement chain being looped over the front sprocket of said bicycle and motorized gear of the sprocket-engaging mid-drive electric powertrain; and g) A partial chain cover for being bolted atop the sprocket-engaging middrive electric powertrain to therein cover the motorized gear and allow access to the chain at all times without removal of said chain cover. The electric conversion kit for a bicycle as claimed in claim 1 , wherein the sprocket-engaging mid-drive electric powertrain comprises- a) A substantively triangular all-weather housing bounded by three substantively flat sides and closed by two opposing faces, said sides and faces being casted in-situ and alternatively fabricated by welding suitably cut portions in materials selected among aluminum and mild steel; b) A plurality of suitable apertures within one of the opposing faces of the all-weather housing for allowing bolts to traverse and thereby engage with the set of two clamps, said clamps being priorly affixed onto the downtube and seat tube of the bicycle, to thereby hold the sprocketengaging mid-drive electric powertrain fixedly in position; c) Packaged within the all-weather housing, by bolting to the internal surfaces of the flat sides of the all-weather housing, each among- i. An electric motor, 250 Watt PMDC motor in particular, with a rotatable gear of 98 mm diameter having steel spur teeth at the end of its shaft; ii. A rechargeable battery of rating ranging from 6ah to 30 Ah for powering the electric motor; ill. A 250 watt motor controller for regulating the power fed from the battery to the electric motor in response to the input received from the human-machine interface. iv. Circuits for charging, discharging and signal conditioning of the battery; v. A first port with a screw-on lid presenting a socket therein to receive a utility power supply for charging the battery; and vi. A second port with a screw-on lid presenting a USB socket therein to serve as a 2.1 Amp power outlet of the battery, for powering extrinsic electrical loads, being cell phones, lamps, their likes and equivalents. The electric conversion kit for a bicycle as claimed in claim 2, wherein the plurality of suitable apertures are four oval shaped apertures traversing the sprocket-side face of the all-weather housing, said oval shape allowing a restricted freedom of movement necessary for alignment of the four bolts to be received within the bolt-wells at the back of the set of two clamps. The electric conversion kit for a bicycle as claimed in claim 2, wherein the circuit for charging the battery is one programmed to convert the pedaling input of the user captured as a function of rotation of the motorized gear of the motor into electricity being stored into said battery. The electric conversion kit for a bicycle as claimed in claim 2, wherein the circuit for charging the battery is one programmed to use the utility power received from the first port for charging the battery. The electric conversion kit for a bicycle as claimed in claim 1 , wherein the human-machine interface is a throttle unit consisting of- a) A key-lock for allowing the user to switch the sprocket-engaging middrive electric powertrain reversibly between its ON and OFF states by turning of a key within said lock; b) A throttle body for allowing the user to regulate the propulsion provided by the sprocket-engaging mid-drive electric powertrain by operating said throttle between its fully closed and opened states; and c) A multi-information display module, being a digital display in particular, for displaying information sourced from the sprocket-engaging middrive electric powertrain, said information including the battery status, speed, time, distance travelled by the bicycle. The electric conversion kit for a bicycle as claimed in claim 1 , wherein each between the set of two clamps is made of- a) A first substantially elongated portion having a convex belly along its long axis, and substantively flat sides flanking said convex belly, said flat sides having three apertures each for allowing threaded bolts to traverse through; b) A second substantially elongated portion having a convex belly along its long axis, and substantively flat sides flanking said convex belly, said flat sides having three internally tapped wells for receiving the threaded bolts from the first substantially elongated portion and two internally tapped bolt-wells on its back side for receiving the bolts used for affixing the sprocket-engaging mid-drive electric powertrain in position; and