| JP2005192374 | AUTOMOBILE RUNNING BY WIND POWER GENERATION |
| WO/2002/020298 | SYSTEM AND METHOD FOR POWER GENERATION |
| JP2002316626 | WIND FORCE BRAKE DEVICE |
t Claim:
1. An electrically operated vehicle, in which the traction being provided by one or more drive motors operating from batteries, the vehicle further comprising a wind operated battery charging system having one (or) more fans driven by the air stream generated by the vehicle motion and /or the headwind linked by a speed controlling means with a generator system having one or more generators wherein the drive motor is of a low speed rating, the generator speed rating being equal to or greater than that of said drive motor, the said batteries are being housed in modular, slidable and interchangeable drawer like housings that slide into position in suitable cavities for the purpose provided on said vehicle, the generators and drive motors are connected in asymmetric configuration with the batteries.
2. An electrically operated vehicle as claimed in claim 1 , further comprising a frame upon which the set of batteries placed in the battery housing, the front and rear wheels, an accelerator unit, a brake unit, a driving system with or without a gear mechanism are mounted.
3. An electrically operated vehicle as claimed in claim 2, wherein the rear wheels and the driving system are coupled such that a cogged belt drive extends between the drive motor and the gear mechanism and a sprocket chain drive extends between the gear mechanism and the rear wheel.
4. An electrically operated vehicle as claimed in claim 2, wherein the rear wheels are directly coupled with the driving system with the belt or sprocket drives extending between them without gear mechanism.
5. An electrically operated vehicle as claimed in claim 2, wherein the rear wheels are directly mounted on the drive motor shaft.
6. An electrically operated vehicle as claimed in claim 2, wherein the accelerator system comprises a current regulating unit that regulates the current to the drive motor.
7. An electrically operated vehicle as claimed in claim 1 , wherein the drive motor includes permanent magnet type DC motor.
8. An electrically operated vehicle as claimed in claim 1 , wherein the drive motor includes geared DC motor.
9. An electrically operated vehicle as claimed in claim 1 , wherein the speed rating of the drive motor does not exceed 2500 rpm.
10. An electrically operated vehicle as claimed in claim 1 , wherein the electrical generator is a DC (or) AC type.
11. An electrically operated vehicle as claimed in claim 10, wherein the AC type electrical generator includes an alternator.
12. An electrically operated vehicle as claimed in claim 10, wherein the DC type electrical generator includes a dynamo.
13. An electrically operated vehicle as claimed in claim 1 , wherein the generators in the generation system are preferably of the same power and speed rating.
14. An electrically operated vehicle as claimed in claim 1 , wherein the sum of the rated speeds of the plurality of generators is equal to or greater than the rated speed of the drive motor.
15. An electrically operated vehicle as claimed in claim 1 , wherein the fans in the wind operated battery charging system are of axial flow type with three, four, six or more blades having fixed (or) variable pitch.
16. An electrically operated vehicle as claimed in claim 1 or claim 15, wherein the fans in the wind operated battery-charging system includes multistage type.
17. An electrically operated vehicle as claimed in claim 1 , wherein for a two wheeler vehicle, one or more fans coupled with one or more generators through a speed controlling means are mounted in the front on the wheel fork at the tapering end of the conical arrangement enclosing the controlling means and the generation unit.
18. An electrically operated vehicle as claimed in claim 1, wherein the speed controlling means is a multiple ratio gear box and/ or clutch and/or flywheel.
19. An electrically operated vehicle as claimed in claim 18, wherein the multiple ratio gearbox is manually operated (or) activated by a linkage from the drive gear box and is provided with a manual override.
20. An electrically operated vehicle as claimed in claim 18 r wherein the activation of the gear box is by a sensing means that senses the fan speed, the generator speed, the vehicle speed, the output voltage of the generator for a predetermined limit.
21. An electrically operated vehicle as claimed in claim 19, wherein the manual override is through foot or hand operated levers.
22. An electrically operated vehicle as claimed in claim 18, wherein the clutch is a magnetic (or) centrifugal type.
23. An electrically operated vehicle as claimed in claim 22, wherein the magnetic clutch is operatively linked to the battery voltage and the speed of rotation of the fans (or) generators.
24. An electrically operated vehicle as claimed in claim 23, wherein the magnetic clutch is deactivated when the battery voltage exceeds a predetermined value and / or is also linked by a sensor to the fan speed (or) generator speed such that when the fan (or) generator happens to be running slow the generator is electrically cut off from the batteries.
25. An electrically operated vehicle as claimed in claim 1 , wherein the fans and generators in the wind operated battery-charging system is coupled in various configurations.
26. An electrically operated vehicle as claimed in claim 25, wherein the configuration includes one fan driving a single generator through a cogged belt drive (or) two fans with each fan driving a dynamo with the two dynamos connected in series (or) a single fan driving a set of dynamos.
27. An electrically operated vehicle as claimed in claim 1 , wherein the said batteries are mounted within the modular drawer like chambers that are detachably mounted on the vehicle so that the changing of batteries is easily and quickly performed by mere pulling out of the drawer like member.
28. An electrically operated vehicle as claimed in claim 27, wherein the battery module comprises a drawer type chamber in which the battery is placed and secured.
29. An electrically operated vehicle as claimed in claim 27, wherein an automatic electrical engagement takes place when a drawer member is slid into position within the housing.
30. An electrically operated vehicle as claimed in claim 29, wherein the electrical engagement is achieved by means of plugging-in-socket system which comprises spring biased contact members located on said cavities engaging with corresponding contact members located in said modules, the said contact members located on cavities are connected with the vehicle electrical system.
31. An electrically operated vehicle as claimed in claim 27, wherein the module comprising jack connections are connected to the battery terminals when the battery is placed therein, the said jacks are wired within housing to contacts located at the rear of said module housing.
32. An electrically operated vehicle as claimed in claim 28, wherein the module is designed to hold one (or) more batteries.
33. An electrically operated vehicle as claimed in claim 1 , wherein the one (or) more generators of the wind operated battery charging system, the batteries and the one (or) more drive motors are connected in an asymmetric configuration whereby the generation unit is not connected such as to come directly across the principle load viz., drive motor.
34. An electrically operated vehicle as claimed in claim 33, wherein the asymmetric configuration is the connection in which either the generator supplies to less number of batteries (or) alternatively the drive motor draws current from less number of batteries present in the set.
35. An electrically operated vehicle as claimed in claim 33, wherein when the generator is connected across the full series battery set while the drive motor draws current from one (or) more batteries of said set but not from the whole set, the remaining batteries of the set is connected to supply other loads such as lighting.
36. An electrically operated vehicle as claimed in claim 33, wherein if the generator is connected to charge lesser number of batteries in the set, after the charging is complete, a switching means operating manually (or) automatically switches the generator to charge the remaining batteries in the set.
37. An electrically operated vehicle as claimed in claim 33, wherein the generators are connected such that one of the said generators charges one half of the battery set while the other charges the second half of the battery set.
38. An electrically operated vehicle as claimed in claim 1 , wherein the output of the wind operated battery charging system is connected to recharge a first set of batteries which in turn charges a second set of batteries that are feeding the drive motor, with the terminals of the charging system and the drive motor isolated by diodes.
39. An electrically operated vehicle as claimed in claims 1 to 38 and as substantially described and illustrated by the accompanying drawings. |
"AN ELECTRICALLY OPERATED VEHICLE HAVING A WIND-OPERATED
BATTERY CHARGING SYSTEM"
Field of the invention:
This invention relates to an electrically operated vehicle having a wind-operated battery charging system.
This invention is relevant to a vehicle wherein the prime mover comprises one or more DC motors and wherein the said DC motor(s) is battery-operated. Said vehicles may be for road, rail, sea or air or combinations thereof. This invention can be easily and simply adapted to all said vehicle applications.
This invention is also applicable to vehicles where the prime mover DC motor is mains operated or where the same is an AC motor.
The invention is relevant to two-, three-, four- and higher order multiple wheel vehicles.
Some aspects of this invention are also applicable to a vehicle wherein the prime mover is an internal-combustion(IC) engine.
However, in the further description herein below, reference is made mainly to a two- wheeler vehicle wherein the prime mover is a DC motor that is powered by the vehicle batteries. This is in the interests of clarity and conciseness and is without any limitation to the scope of the invention.
Discussion of the Prior Art:
In an EV(electric or electrically-operated vehicle) the traction power comes from a battery or a set of batteries. EVs are characterized by their limited speed and distance range. Increase of speed and range in EVs can be achieved by the adoption of larger battery packs but this comes with the disadvantages of increased space requirements for the battery pack on the vehicle and increased vehicle weight.
To increase the range of such vehicles and in the interests of energy conservation regenerative braking has been adopted in prior art to recover the kinetic energy of the vehicle, which would otherwise be lost during braking of the vehicle.
The regenerated energy is returned to the vehicle battery pack. Energy is also recovered during downhill running of the vehicle and during decelerations. Non conventional means of energy conservation such as utilising the solar power is also employed in combination with various other recovery techniques.
An example of regenerative braking is the vehicle disclosed in US Patent No. 3,878,973(D.C. Liounts et al). The vehicle comprises a wind-based battery charging system wherein regenerative energy is recovered by a fan activated by the travel- occasioned stream of air. A flywheel in the system also helps in the recovery of the regenerative energy. The fan also utilises energy available in a head wind if the same is present during the movement of the vehicle. The recovered energy extends the range of the battery pack.
US Patent No. 5,680,032 (Pena) teaches an electrically powered vehicle wherein during forward motion of the vehicle air is captured at the front of the vehilce and channeled to one or more turbines. The motive power of the air rotates the turbines, which are rotatably engaged with a generator to produce energy that is used to recharge the batteries. The generator is also rotatably engaged with a flywheel for storing mechanical energy while the vehicle is in forward motion. When the vehicle slows or stops, the flywheel releases its stored energy to the generators, thereby enabling the generator to continue recharging the batteries. This invention utilises two modes of recharging the batteries to meet the energy requirements.
US Patent No. 5,920,127 ( Damron et al) teaches an electric vehicle with a system that will provide energy to the battery pack while the vehicle is being driven by using an energy conversion system based on unenclosed multibladed small diameter propeller actuated high output generator. An electric car is described with an apparatus for capturing energy from the wind and converting such energy into electric energy.
The apparatus consists of a multibladed small diameter propeller, an extension shaft, a generator with a centrally located armature shaft on which shaft extends and provides means by which the propeller is mounted on a common axle with shaft.
US Patent- No. 5,986,429 (MuIa, Jr.) teaches an electric vehicle comprising a wind tunnel positioned longitudinally along the frame structure of the vehicle, A plurality of wind driven generators are situated within the tunnel adapted to convert the stream of air therein to electric energy. The battery system further comprises regenerative braking system and solar panels for converting braking force and solar energy to produce electric energy.
US Patent No. 6,740,988 (Tseng) teaches an energy generation device for mobile carriers. The energy generation device contains atleast one rotating mechanical unit with a fan set with a configuration such that the vertical axis of the rotation plane is roughly parallel to the following direction of the external fluid. The central axis is connected to a speed - reduction gear set for reducing the rotational speed of the central axis. The gear set uses a power transmission axis to connect to the power generation unit for generating electrical power.
The Indian patent application No. 142/MAS/2003 of 21 st Feb. 2003 by this inventor also discloses, a vehicle provided with a wind-based battery recharging system, wherein regenerative energy as well as energy in the head wind, if any, is recovered by means of a fan and dynamo(DC generator) arrangement and charged into the vehicle battery pack.
Most of the prior art vehicles employs plurality of bulky wind driven generator units having one or more turbines located within wind tunnel and also makes use of two or more modes of generation utilising the regenerative , solar and wind energy for recharging the batteries. The above cited prior art patents are herein included as references.
Summary of the invention:
This invention has attempted to enhance the battery range, in comparison to prior art vehicles/devices with much simpler construction by minimizing the drawal of current from the battery as much as possible; by preventing/minimizing breaks in the battery charging current to the extent possible and further by ensuring a substantially uniform charging current to the battery from said wind-operated battery, charging system,
This has been achieved in the invention by the adoption of:
i. iow-speed drive motor(s) for the vehicle; ϋ. a higher rated speed for the dynamo of the wind-based battery recharging system of the vehicle than that adopted in the prior art; and iii. a plurality of dynamos in the wind-based battery charging system of the vehicle, instead of the one conventionally used in prior art vehicles.
These are novel features of the invention and are elaborated further herein below.
A DQ drive motor of an EV draws a greater current during starting of the vehicle than during cruising of the vehicle, on level ground. This inventor has observed that said increase is lesser if a low speed drive motor is used and furthermore, the lesser the speed rating of the prime mover motor the lesser the said increase. In other words, for providing the same starting torque a drive motor of a lesser speed rating draws less energy from the battery source during the starting operation than a drive motor having a higher speed rating and the same power.
What is said for the starting process also applies to acceleration periods and during hill- climbing stages of the vehicle travel, When one. considers the several start-stops in a typical journey in a city this adds up to a good amount of saving in battery energy if low- speed DC drive motors are adopted. Added to this is the energy saving realized in the accelerations and gradient traverses.
Another fact observed by this inventor is that for the same power a low speed DG drive motor generates a greater torque than a high-speed one, The availability of greater torque for the same power rating allows elimination of a number of drive system components leading to simplification of the vehicle design and reduction in the vehicle weight. The drive system in the vehicle of the said Indian application comprises a four speed gear box with two sprocket drives, one provided before and the other after said gear box.
Thus, the adoption of low speed drive motors (prime movers), according to the invention, in EVs offers the following design alternatives not available in prior art EVs.
i. . reduction of the speed ratios of said sprocket drives and even elimination of one, or both, said sprocket drives; ϋ. substitution of a 3-speed or even a 2-speed gear box in place of the 4-speed gear box of said Indian specification and even elimination of said gear box altogether; and in. elimination of the whole drive system with direct coupling of the drive motor and the driven wheel.
By adoption of one or more of these design alternatives made available by this invention, one can achieve different objectives/advantages, such as,;
i. reduction of vehicle weight; ϋ, simplification of the drive system and reduction in drive losses; ϋi, simpler vehicle configuration with simpler assembly, easier maintenance, lower aerodynamic drag- and other cost advantages. .
In the specific embodiment described herein, it will be observed that the 4-wheel gearbox has been retained so as to offer flexibility of operation and saving in power and for higher operating speeds. This is without limitation to the scope of the invention and as mentioned, the invention allows the option of total elimination of the gear box.
In ail prior art vehicles, including the vehicle described in said Indian patent application, the speed of the prime mover DC motor of the electric, vehicle is about 2500-3000 RPM, that is, close to the idling speed of the equivalent vehicle having an IC engine. This correspondence of speeds between electric vehicles and their IC equivalents appears to have been adopted for the reason that it simplified the design of the drive system of the electric vehicle. With the DC motor rated at 2500-3000 RPM 1 that is, close to said idling speeds, it becomes possible to adopt the drive system of the IC vehicle almost without any change for the electric vehicle.
Possibly, for this reason, prior art has not looked into the question of adopting lower speeds for the. prime mover DC motors, Prior ait has not considered the suitability of low speed motors for electric vehicle prime mover applications. No prior art document appears to have contemplated, discussed or disclosed the adaptability and advantages of adopting low-speed motors as. prime movers in electric vehicles or in EVs having wind-based battery recharging systems.
As mentioned, prior art has therefore adopted the high speed range as the standard for electric vehicles, This invention is apparently the first to consider the low speed range and to look into the suitability and desirability of said low-speed motors for said prime mover applications and in adoption of the same. This is novel.
In this description, the term 'high speed 1 in relation to the DC prime mover motors is intended to refer to speeds of 25.QQ RPM and above while the term 'low speed' is intended to refer to speeds not exceeding about 2500 RPM.
This aspect of the invention, namely, the adoption of (ow speed DC motors as prime movers is applicable to electric vehicles both with and without said wind-operated battery recharging system.
In this specification, the terms 'charging' and 'recharging' in relation to batteries may be considered synonymous unless otherwise required by the context,
The second aspect of this invention, is the consideration of the rated speed of the dynamo in the wind-operated, battery charging system, At cruising speeds, the dynamos in the prior art vehicles would appear to operate in the speed range of about 150-400 rpm. This is with a substantially nil head wind. The speeds would be somewhat higher when a head wind i§ present, In the cited US specification, as a 2;1 speed reduction means is provided between the fan and the dynamo, the dynamo speeds can be expected to bθ in the range of 150-250 rpm. In the cited Indian specification, the fan and dynamo are directly coupled and the dynamo speeds in this arrangement can be expected to be around 300-400 rpm. The objective in prior art seems to be to keep dynamo speeds low so as to prevent damage to the dynamo and batterie(s) due to overrunning thereof at high vehicle speeds. Prior art does not appear to have contemplated, or considered the suitability of adopting higher dynamo speeds obtained by using a step up gear mechanism between the fan and alternator/dynamo units and appears to be unaware of the advantages thereof,
This inventor observes that when the said dynamo speeds are low, any increased torque demand by the vehicle during running, such as during acceleration or for hill-climbing, tends to either stall the dynamo or, alternatively cause a substantial fall in the speed thereof. The consequence of this is either a stoppage of the battery charging current flowing from the dynamo or a considerable drop in the same, It will be observed that any dislocation, either stoppage or drop, in the battery charging current represents a loss in the energy returning to the battery and is, therefore, a potential reduction of the vehicle range, During a vehicle, journey, such stoppages/dislocations, particularly in an urban environment, add up to a considerable shortfall in battery charging and therefore its range. By adopting higher dynamo speeds, this invention substantially eliminates said stoppages and prevents/minimizes said drops in the charging current leading to an increase of the battery range, that is, vehicle range.
This invention is the first to consider high dynamo speeds, that is, dynamo speeds equal to or greater than that of the associated vehicle motor and preferably greater than 75Q rpm. This is novel and ensures continuity and substantial uniformity of the charging current unlike in the prior art vehicles/devices. This fact is particularly important during starting, accelerating or hill climbing situations when the dynamo in prior art vehicles tends either to stall or slow down and cause a fall in the battery charging current.
Where a plurality of dynamos are used as called forth in the third aspect of the invention discussed herein below, this aspect requires that the sum Qf the rated speeds of the dynamos be considered and that said sum must be equal to or greater than the said vehicle motor speed. If, for example, two dynamos are employed, the sum of their rated speeςjs must be equal to or greater than the. motor speed, If, however, the two dynamos are of different power rating then a weighted sum needs to be taken according to the invention. This invention, preferably, calls for two identical dynamos, that is of equal power and speed rating and preferably identical to the drive motor,
This invention observes that the higher the said dynamo speed in relation to said drive motor rated speed, the less the severity of said stalling of the dynamo or the drops in speed thereof. A higher dynamo speed reduces/eliminates said stallings and said speed drops and helps stabilise the battery charging current over said accelerating and hill- climbing situations, Therefore, preferably, said dynamo speed is equal to, or higher than the rated speed of the drive motor.
The above cited remarks and conclusion are relevant to permanent magnet DC motors, DC field motors and to reluctance, motors, The object of this aspect of the invention is to ensure a substantially continuous battery charging current.
The basis of the third aspect of the invention is the observation by this inventor that the provision of two or more dynamos in series in place of one helps in providing even greater stabilization of the charging current and in keeping it uniform and furthermore, reduces the occurrence of stalling. Preferably, the charging system comprises a pair of dynamos in series and preferably said two dynamos are of the same voltage, current, speed and power rating as the one that they replace.
A yet another observation of this inventor is that the stability of the battery charging current is further improved if the said dynamo of the wind-operated battery charging system is not connected such as to come directly across the principal load in the vehicle, namely, the drive motor. This aspect of the invention requires that the said dynamo be connected across any one, or more, of the batteries of the vehicle pack but not across the entire set, said drive motor being connected across the whole of said set. It is assumed that the batteries of said set are ail connected in series.
This aspect of the invention is referred to hereinafter as the asymmetric connection. In a symmetric connection, the dynamo, would be conne.ete.ci across a set of batteries in series and the entire said series would supply current to the drive motor. In an asymmetric connection, either the dynamo supplies to less number of batteries or, alternatively, the drive motor draws current from less number of batteries than are present in the set.
It will be seen that the alternative configuration that follows from this aspect of the invention is that the dynamo is connected across the said full battery set while the said drive motor is connected across any one or more of the batteries of said set but not across the whole set. Where the batteries in the set are connected in other arrangements, say, parallel or series-parallel the concept of this aspect of the invention is easily extended to such arrangements.
A preferred arrangement is where said dynamo is connected across the full series battery set while the drive motor draws current for operation from one or more batteries of said set but not from the whole set, the remaining batteries of the set being connected to supply other loads in the vehicle such as for example, the lighting.
Another preferable alternative arrangement is that the output of the alternator/ dynamo is connected across a set of batteries which recharges another battery set supplying current to the drive motor. The generation unit and drive motor are isolated by a diode connected in between the two battery sets. Thus the drive motor unit does not form a direct load across the generator supply.
It will be observed that numerous combination configurations are possible within the scope of this aspect of the invention. If in an arrangement, the dynamo is connected to lesser number of batteries than the whole set then the invention provides for a switching circuit that would manually, or automatically, switch the dynamo to enable charging of the remainder of the batteries of the set,
Another preferred arrangement is one where the battery charging system comprises two clynamos in series, The two dynamos are connected such that one charges one half of the set while the other charges the other half.
To summarise, the three aspects of the invention discussed hereinabove are:
a. adoption of a low speed drive motor as prime mover; b. adoption of a dynamo of a higher speed rating, preferably equal to or greater than the drive motor speed rating, and c. adoption of two or more dynamos in place of one, said two being preferably of the same rating a§ the one they replace and being preferably connected such that each charges one half of the battery set of the vehicle.
The advantages realised by adoption of the abovementioned aspects of the invention are;
1. simpler construction of the vehicle; j. reduction in vehicle weight and cost;
2. improvement of vehicle profile and reduction of air resistance(drag);
3. elimination of the possibility of stalling and uniformity of the battery charging current;
4. ease of assembly and maintenance;
5. improved energy efficiency in view of the above; and §, simplification, or even elimination, of the gear box,
The three aspects of the invention described hereinabove are based on the practical observations and investigations by the inventor, Thus the explanations of the effects offered are by way of suggestion and this invention is not dependent on said suggested mechanisms.
It will be observed that one or more aspects of the invention are applicable inter alia to:
i. an EV with a wind-operated battery charging system; ii, an EV without a wind-operated battery charging system;
iii. and IC engine vehicfe with a wind-operated battery charging system; iv. an EV where the drive motor operates from a mains system; v. an EV having an AC drive motor and with/without a wind-operated battery charging system; Yi. an EV having an alternator in the wind-operated battery charging system thereof; vii. hybrid vehicles having wind-operated battery charging systems or electric drive systems or both; and others,
A yet another aspect of the invention is the modular system of housing for the vehicle batteries. In this arrangement, the vehicle batteries are mounted within modular drawer- like members that are detachably mounted on the vehicle. A said module may hold one battery each or a plurality of batteries although as would be observed the convenience is reduced when large modules carrying more than one battery each are adopted.
The object of the said arrangement of the invention is to make these modules easily detachable so that a battery change is easily and quickly performed on a vehicle by mere pulling out of the drawer-like member(drawer member) housing the particular battery to be changed. After removal of said battery, another module containing a new battery, or a recharged battery or a serviced battery as applicable is slid into the housing provided on the vehicle for said modules.
Considering a battery module provided by the invention, it comprises a drawer-type chamber wherein the battery is placed and secured if required. Otherwise, said member may be of such dimensions and configuration and comprising means such that no separate securing means are required. The vehicle comprises cavities(housings) for receiving said drawer chambers, During battery changeovers said chambers holding the new, recharged or serviced batteries are slid into said cavities.
When a said drawer member is slid into position within a housing electrical engagement automatically takes place. This is by means of contact members located on said modules engaging with corresponding spring-loaded contact members located in said cavities, said contact members of the cavities being connected with the vehicle electrical system. Each module comprises jacks that are used to connect to the battery when the
same is placed therein. Said jacks are wired to the said module contacts of the respective drawer members, After a battery is placed in the module thereof, it is handled, moved, carried, charged, tested etc in position in the said module thereof. A module may be designed to hold just one battery or a plurality thereof within the scope of the invention, Preferably, each battery is associated with its own individual module housing.
The advantage of the module system of the invention is that no connection or disconnection of the battery is required when for example, replacing a battery or taking the battery out for recharging or maintenance or for any other purpose. Once a battery is mounted in the module thereof, it is handled as mounted in the said drawer member housing thereof, This invention envisages that service stations, petrol stations and other service providers would hold stocks of batteries within said drawer members for easy replacement/change of vehicle batteries. Thus, a vehicle needing a battery change or battery recharge would drop into a service station where the batteries needing change would be slid out of their cavities and a set of new, charged or serviced batteries, as required, would be slid into position. The invention, thus, also provides for a common pool of batteries to be in interchangeable circulation between a set of vehicles and a set of said service stations, petrol stations or charging stations.
According to the invention, therefore, there is provided an electric vehicle for locomotion by land, sea and air or combination thereof, the traction therein being provided by one or more drive motors operating from batterie(s), the vehicle further comprising a wind- operated battery charging system comprising inter alia one or more fans driven by the air stream generated by the vehicle motion and/or the headwind if present, and a generator system, and being characterized in having at least one of the following features:
a. the speed rating of the drive motor(s) not exceeding 2500 RPM;. the generator speed rating being equal to or greater than that of said drive motor and where a plurality of said generators are employed, the weighted sum of their speed ratings being so;
b. said generator system comprising a plurality of generators: with the said generator Qf the wind-operated battery charging system i§ not connected such as to come directly across the principal load in the vehicle, namely, the drive motor and
c. said batteries being housed in modular, slidable and interchangeable drawer-like, housings, that slide into position in suitable cavities for the purpose provided on said vehicle, said housings and cavities comprising electrical contacts that engage automatically and provide electrical connection between the batteries and the electrical system of the vehicle upon said sliding into position.
Description of the invention:
The vehicle of the invention comprises a frame upon which the set of batteries, the front and rear wheels, the drive system and other systems and equipment are mounted, The frame may be of any of several different configurations and cross-sections provided in prior art. Any of the conventional frames in use may be easily adapted to the special requirements Qf the vehicle of the invention such a§ the mounting for the fan and the dynamo system (battery charging system) with the control and instrumentation elements therefor, the drive system between the drive motor and the driven wheel, the set of ca,vities(hQusjngs, to hQuse said drawer-like battery housings which carry the batteries), controls for the drive motor and drive system, if any and other parts and components.
Said battery housing unit (block) comprises cavities one each for each of the batteries in the vehicle battery set Said cavities hold drawer-like members, also referred to as battery modules or module housings that can be easily slid in and out there from. Said drawer-like members (module housings) actually house the vehicle batteries, one per housing. Other configurations are within the scope of the invention,
Said housing block is preferably located in the middle portion of the vehicle in the interests Qf uniform weight distribution, The housing block is a generally reetangylar- section box like member in which said cavities are located that hold said drawer
members (battery modules) carrying the batteries. They are slid in place and secured by convenient securing means, Other configurations of said frame, the said housing and the location thereof are within the scope of the invention.
Support members such as brackets are provided either on said housing block or the frame for mounting Qf the drive motor and drive system members such as the chain &, sprocket drive, the cogged belt drives and the drive gearbox. The cogged belt drive extends between the drive motor and the gearbox while the sprocket drive extends between the gearbox and the rear (driven) wheel, A 4-speed gearbox has been adopted in the embodiments described one but other specifications and configurations of the gearbox are within the scope of the invention. The invention also provides for elimination of the gearbox and/or the beltfeprocket drives. Other configurations and arrangements of the various parts of the drive system and components are within the scope of the invention such as, for example, the use of a geared or non-geared motor directly driving the rear wheel,
This invention provides for a drive motor of speed rating below 2500 RPM. In the embodiment described herein the drive motor speed selected is, 1500 RPM, Within the scope of the invention, drive motor speeds can be selected (500 to 750 RPM) that would allow elimination of one or more of the drive system members and direct coupling of the motor and the driven wheel, A geared DC drive motor in general alignment with the driven wheel is also within the scope of the invention.
According to the invention, the lower the speed rating of the drive motor the better, in the embodiments described herein, a drive motor of 24V (or) 48V / 1500 RPM rating has been selected. The pair of dynamos selected for the battery charging system are also each 24V (or) 48V/ 1500 rpm rating. The said three components (drive motor and dynamos) are. permanent magnet type and are interchangeable in view of their identical ratings. This offers inventory and maintenance advantages. Other motor specifications and configurations such as field wound DC motors or reluctance motors are within the scope of the invention as are also other speed and voltage ratings. An AC drive motor suitable for the traction with suitable DC to AC conversion circuitry also can be used.
The battery charging system comprises essentially a fan driven by the wind generated by the vehicle motion and. further by a head wind if and when present. The fan is drivingly linked to the dynamos through a speed increasing means. The invention provides for a plurality of dynamos in the battery charging system. Preferably the system comprises two dynamos as in the preferred embodiment described. Preferably, said two dynamos and the drive motor are identical in construction and ratings and are interchangeable.
Said fan is of the axial flow type having three, four, six or more blades. Within the scope of the invention, there may be a plurality of fans, for example, two fans each driving a dynamo. Alternatively, the two fans may drive the two dynamos together. The fans may be mounted in such an arrangement which reduces the be of- fixed pitch or variable pitch blades and the fan may aerodynamic drag and also houses the generator units, An aerofoil bladed fan may also be used. Various fan-dynamo configurations are .feasible within the scope of the invention. _.ln o.ne_ embodiment described .herein below, one fan drives a single dynamo through a cogged bejt drive, Two fans are provided in another wherein each fan drives a dynamo with the two dynamos connected up in series.
In the preferred embodiment, the fan is mounted on a shaped arrangement- at- the front on the wheel fork and is coupled with the dynamos located below through gears that provide a 2:1 enhancement of speed to the dynamos. Other arrangements are feasible within the scope of the invention.
A clutch may be interposed between the fan and the dynamos. Similarly, a flywheel may be provided between the fan and the dynamos, A flywheel would increase recovery of the energy during braking but would also add to the vehicle weight. The clutch may be centrifugal type or other types. In the preferred embodiment, a magnetic type clutch is provided that is operatively linked to the battery voltage and the speed of rotation of said fan/dynamos. The magnetic clutch is deactivated when the battery voltage exceeds a predetermined value corresponding to full-charge status of the battery set, It is also linked by a sensor to the fan speed or the dynamo speed such that when the fan happens to be running slow (or the dynamo as the case may be) the dynamo is electrically cut off from the battery set.
Multi-stage fans may also be used in the vehicle of the invention.
This invention also provides for a fan gear box located in the drive from the fan(s) to the dynamo(s). Said gear-box may be 2-speed, 3-speed, 4-speed- or other and may be manually operated or activated by a linkage from the drive gear box. If so linked, a manual override is preferably provided.
Said activation of the fan gear box may be by means of a sensor that senses the fan speed , the dynamo speed- or- the vehicle speed or by a sensor that reads the output voltage of the dynamo(s) for a predetermined limit . Said manual operation or override may be through foot-operated or hand-operated levers.
The two dynamos may be connected in series and wired to the battery set such that irϊey charge the entire series of batteries. Alternatively, they may be wired such that one charges some of the batteries independently and the other similarly charges the remainder. An asymmetric arrangement wherein the two dynamos together charge only some of the batteries in the set while the others are charged by other means such as a main charging is also feasible. Alternatively, the vehicle may comprise a switching system by means of which charging of the different sub-sets of the battery set may be carried out. In general, according to the invention, it is preferable that the two dynamos charge separate groups of batteries and not a common group. In the preferred arrangement, one dynamo charges two batteries in series of 12 V each while the other charges the other two of the set of four batteries. Another preferable alternative arrangement is that in a single dynamo generator system, the dynamo is arranged to charge a set of batteries, this set of batteries in turn charges another battery set which is supplying current to the drive motor. The dynamo and drive motor are isolated by a diode connected in between the two battery sets. The division of the battery set for charging purposes improves the performance of the dynamos and ensures a more stable battery charging current. As mentioned hereinabove, numerous combinations of electrical connections constituting said asymmetric connection between dynamo(s), batteries and- drive motor are possible. Different types of batteries with different specifications are adaptable to the vehicle of the invention.
The accelerator system, that is, power control system may comprise any of the conventional systems in EVs. In the embodiments, described herein below, the accelerator system comprises handlebar control by means of a rotatable hand grip. This operates a rheostat which controls the motor current through a Mosfet circuit. The Mosfet-based motor current control system i§ described in the said Indian patent application No. 142/MAS/2003 of 21.2.03 of this inventor.
The vehicle of the invention comprises several other major and minor systems and components such as the braking system, the vehicle electrical system and the vehicle control console on, or near, the handlebar and others. In respect of these, any of the known systems can be easily adopted in the vehicle of the invention.
In order to provide a clearer understanding of the invention, a few embodiments thereof will now be described without limitation tQ the scope of the invention, and by reference to the accompanying drawings wherein like numerals represent like parts, and wherein:
Fig. 1 shows a side view of the assembled vehicle of the invention;
Fig. 2 shows a front view of the assembled vehicle of the invention;
Fig. 3 shows the side perspective view of the fan-dynamo system of the vehicle of the invention;
Fig. 4 shows the front view of the fan-dynamo system in the vehicle of the invention;
Fig. 5 shows an alternative embodiment of the fan-dynamo system of the invention, wherein a gear box is provided between the fan and dynamos;
Fig. 6 shows, the wiring diagram of the battery charging system and the motor drive system control system in the vehicle of the invention;
Fig. 7 shows alternative embodiment of the wiring diagram of the battery charging system and the motor drive control system of the invention, comprising two fans each linked to a dynamo;
Fig. 8 shows a perspective view of a drawer-type, interchangeable module battery housing and two views of a battery housing cavity of the invention, wherein the module is shown partly introduced in one and fully positioned in the other;
Fig. 9 shows the front and rear views of the housing block of the invention comprising cavities for housing four module battery housings; and
Fig. 10 shows the detail of accelerator system (motor power control system) in the vehicle of the invention.
Reference numeral (1) of Fig. 1 denotes the frame of the two-wheel vehicle of the invention, to which is attached, the front fork (2), On the front fork (2) and the frame (1) are mounted the battery charging system generally denoted by numeral (3), the battery housing block generally denoted by numeral (4) and the drive system of the vehicle generally denoted by numeral (5), Said drive system (5) comprises drive motor (6) connected to rear wheel (7) through a cogged belt drive (8), drive gear box (9) and sprocket drive (10). Battery housing block (4) holds the set of vehicle batteries (11) which are of the lead-acid type.. The vehicle batteries are of the sealed tubular type but other types are easily adapted for the vehicle of the invention. Each battery is of 12 V rating thus giving a 48V power supply for the drive motor (6). Within the scope of the invention, said batteries may be of other types and with other specifications and ratings, Similarly, the battery pack of the vehicle may comprise one battery or a plurality thereof. The drive motor is of the permanent magnet DC type but can be of other types within the scope of the invention.
The battery charging system (3)(Figs. 6 BJ) comprises axial-flow type fan (12) which is linked tg two dynamos (DC generators) (13), Said two dynamos are on a common cogged belt drive (35) from the fan (12) and rotate at the same speed. The two dynamos are connected in series and are each rated 48V output at a speed of 1500 rpm. Being in series the two together provide a 48V output at a speed of about 750 rpm. Interposed between the fan (12) and dynamos (13) is a magnetic clutch (14). The magnetic clutch (14) isolates the fan from the dynamos (13) under certain predetermined conditions. This is elaborated further herein below,
(Under normal cruising conditions, that is at vehicle speeds of about 50 Kmph, the fan- dynamo gear drive (35) provides about 2;1 speed-up for the dynamos 13),
is
The accelerator system of the vehicle comprises a rheostat control (16)(Fig. 10) that varies the current to the drive motor (6). Said rheostat control operates through a MOSFET control circuit (15) that regulates the current to the motor (6). The rheostat control is mounted on the handle bar (18) of the vehicle. The accelerator system of the vehicle, as a whole is generally denoted t>y numeral (17)-
Also mounted on handle bar (18) is brake lever (19) that connects to the brake shoes located in the drums (20, 21) for the front and rear wheels respectively.
The battery housing block (4) (Fig. 9) comprises four cavities (22) wherein are housed the four batteries (11) of the vehicle. Each battery (11) is housed in a module drawer- type box housing (23) which, in turn, is housed in a said cavity 22). A battery is placed in, slid into a said module drawer type box housing (23) and secured in place. Said box housings (23) are of modular construction and are interchangeable. Each battery is handled always in position within the said housing (23) thereof, whether the handling operation, is charging or maintenance or replacement or removing/placing the battery in the vehicle. Storage of the batteries is also done with them in position in their respective housings. The object of this aspect of the invention is the provision of a common pool of batteries in their respective housings for a common community pool of vehicles, the batteries within their housings being handled by a common pool of garages and service stations.
Said battery housing boxes (23) are slidably mountable in their cavities. After a box is slid into position it is. secured in the cavity, Each said box comprises jack connections that are connected to the battery terminals when a battery is placed therein. Said jacks are wired within housings (23) to contacts (25) located at the rear of said module housings. Spring-biased contacts (26) are provided at the back of each said cavity (22), When a box(module housing) (23) is slid into position, the contacts (25) on the module housing box lock with the sprung contacts (26) located within the cavity (22) and remain engaged under spring pressure, The cavity contacts (26) are wired such that they connect the four batteries (11) in series and further connect the battery set to the electrical system of the vehicle. Said module housings (23) comprise swing handles (39) for ease and convenience in handling, After a said battery module housing (23) is slid into position, the doors (40) of the cavity (22) are closed.
The dynamos (13) are connected to the vehicle electrical system such that one charges one-half of the vehicle battery set, that is, two batteries while the other charges the other two batteries.
A voltage sensor (36)(Fig. 6 &7) is provided for the battery set of the vehicle, it reads the battery status and when the battery is fully charged it de-activates said magnetic clutch (14) such as to cut out the drive from the fan (12) to the dynamos (13). Similarly, a speed sensor (37)(Figs. 3&5) is also wired to de-activate said magnetic clutch (14). Said speed sensor (37) senses the fan speed and Keeps said clutch (14) deactivated till such time as the fan speed reaches a pre-determined value. Thus, the drive from the fan to the dynamos remains cut all the time the fan speed is below said pre-determined value, Both these controls have manual override arrangements.
The drive gear box (9) is a four-speed gear box and is manually operated but can be made automatic.
The other principal parts of the vehicle are front wheel (27), seat (28), console (29) comprising switches, control elements, gauges, indicator and warning lamps etc,, head and tail lamps (30), main switch (31), rear view mirror (32), shock absorbers (24) and coil springs (34) and lever for drive gear box (33).
The vehicle further comprises several major and minor systems and parts required for the safe and efficient operation of the vehicle, These may be of any of the conventional types and designs available in the art.
For operating the vehicle, the main switch (31) is closed. This connects power supply to the motor (6), which is then gently increased by means of the rheostatic control (16) till the vehicle reaches the desired cruising speed.
As soon as the vehicle moves, the fan (12)(Figs. 4 & 5) also begins to turn. At this stage, said magnetic clutch (14) is in the de-activated state and the drive, therefore, is not transmitted from the fan to the dynamos. At said pre-determined fan speed the magnetic clutch (14) engages and the fan begins to drive the dynamos.(13).
The dynamos now generate the battery charging current that charges the batteries. When the batteries reach full charge said sensor (36) cuts out the drive to the dynamos, Also, if the fan speed falls below said pre-determined value at any time during vehicle travel, the sensor (37) deactivates the magnetic clutch (14) and cuts out the drive to the dynamos, As the vehicle speed, increases the necessary gear change in the drive gear box (9) is carried out.
In an alternative embodiment of the fan-dynamo drive system of the invention (Fig. 5), a 3-speed gear box (38) is provided between fan (12) and magnetic clutch (14).. Drive gear box (9) and the fan gear box (38) are linked so as to provide synchronized operation thereof. Lever (33) operates the drive gear box (9) and is linked to the fan gear box (38). Lever (33) also operates the fan gear box (38) and is provided for manual override. A manual override is also provided for the fan gear box (38).
In an alternative embodiment of the battery charging system of the invention (Fig. 7), two fans (12) are provided each separately driving a dynamo (13),
The recharging of the batteries can also be done from an external power source through the main power input means,
Various embodiments and variations other than described hereinabove that are within the art are within the scope of the invention ^
List of parts and identification numbers
1. Vehicle frame
2. Front fork
3. Battery charging system as a whole
4. Battery housing block as a whole
5. Drive system as a whole
6. Drive motor
7. Rear wheel
8. Cogged be.lt drive for drive motor
9. Drive gear box
10. Sprocket drive
U, Lead-acid batteries
12. Fan
13. DC generator(dynamo)
14. Magnetic clutch
15. Mosfet circuit
16. Accelerator(rheostat switch)
17. Accelerator system as a. whole
18. Handle bar
19. Brake lever
20. Drum brake- front
21. Drum brake-rear
22. Cavity for batteries
23. Drawer-like, module housing for battery
24. Connecting jacks for batteries
25. Contacts in battery module housing
26. Spring-biased contacts in cavity
27. Front wheel
28. Seat
29. Console comprising controls., gauges, indicators, warning lamps etc,
30. Head and tail lamps
31. Main switch
32. Rear view mirror
33. Lever for drive gear box
34. Lever for fan gear box
35. Cogged belt drive for dynamos
36. Voltage sensor for batteries
37. Speed sensor for fan
38. 3-speed gear box for fan-dynamo drive
39. Module handles
40. Cavity doors