Bicycle deriving driving force by motor-generator

Disclosed is a bicycle which is a means of short-distance movement favored by men and women of all ages. The present invention is an application of a bicycle having a motor-generator disclosed in Korean Patent Application No. 2009-035298 that the applicant of the present invention filed. Namely, a motor-generator is mounted on a side of the rear wheel of the bicycle, and a control box and a battery are mounted under the main pipe of the bicycle, and a change-over switch and a change speed switch are mounted on the handle of the bicycle. The present invention makes it possible to charge quickly and effectively via a motor-generator that is operated by the bicycle driving force on a downhill or level ground, and with charging made, the rotary force of the motor-generator is conveyed to the rear wheel to generate electric power, so that electromotive force is produced and stored by itself, and the driving force of the bicycle can be obtained by using the stored electric power. Therefore, it is possible to use the bicycle easily and conveniently for a long time, and it has an effect of much reduced leg fatigue even in the case of moving a long distance.

TECHNICAL FIELD

The present invention relates to a bicycle which is a means of short-distance movement favored by men and women of all ages, and more specifically to a bicycle in which a motor-generator is mounted on the rear wheel of the bicycle, and the electric power obtained from the motor-generator is stored in a separate battery, and the electric power stored in the battery is converted into and used for power to rotate the motor mounted on the rear wheel via the action of a change-over switch, so that charging is made by carrying out a power generation action in the case of being propelled by user's power or going downhill, and rotary force is conveyed to the rear wheel when charging is made to obtain an electrical driving force to make it possible to use the bicycle conveniently.

A bicycle is a collective name of relatively light-weight two-wheeled vehicles in which a front wheel and a rear wheel are connected by pipes and the rear wheel is connected to a pedal via a chain sprocket, a derailleur and a chain. When the rider pushes on the pedal, power is conveyed to the rear wheel to generate the driving force of bicycle.

In such a bicycle, the front wheel is connected via a front fork that is connected downward to the lower end of a head pipe, and the rear wheel is connected via a fixed pipe and rear fork that together support a seat. The head pipe and fixed pipe are connected via the combination of a main pipe, support pipe and down pipe.

A handle is placed laterally at the upper end of the head pipe, and handlebars are fixed at the opposite ends of the handle. The chain sprocket and pedal are rotatably joined to the lower end of the down pipe and support pipe, and the derailleur and chain stay are joined to the rotating axis of the rear wheel that is connected to the lower end of the rear fork.

However, such an ordinary bicycle obtains a driving force by relying on a genuine power of user's feet, so riding a bicycle for a long time or moving a long distance causes a feeling of extreme fatigue. Especially for a beginner, there is a problem that long-time or long-distance riding is impossible.

And in order to overcome the limitations that a bicycle has for an uphill path, a multi-stage derailleur is adopted to make it relatively easy to climb a hill or an uphill road. But such a derailleur increases the number of revolutions from the force of pedal conveyed by a chain sprocket, and obtains a force proportional to it to make it possible to climb a hill. Because of this, physical strength is consumed proportionally, and still more kinetic force is required.

Therefore, a recent trend is the marketing of electric bicycles in which driving force is automatically generated by mounting a separate electromotive means on the bicycle and providing the rear wheel with a rotary force from the electromotive means.

Such an electric bicycle comprises a battery for storing electricity by using household electricity and an electromotive means that is rotated and driven by applying the battery electricity. Since the rotary force generated from the electromotive means is conveyed to the rear wheel via a power transmission device, it is designed in such a way that running a bicycle is possible without relying on the user's force.

However, such an electric bicycle cannot be used unless charging work is carried out after finishing riding the bicycle. Therefore, it has a problem that excessive power is consumed for charging and the requirement of a long time for charging results in many limitations in use.

Also, in the case of using an electric bicycle for a long distance or a long time, the battery discharges completely to cause the loss of the function as an electric bicycle, then the bicycle should be run by relying on a user's power as in a conventional ordinary bicycle. Therefore, the user will feel more serious fatigue and more momentum and physical power are required as the weight of the electromotive means is added to the weight of the bicycle, so it is not so efficient.

DISCLOSURE

To solve the above-mentioned problems, the present invention is an application of a bicycle having a motor-generator disclosed in Korean Patent Application No. 2009-035298 that the applicant of the present invention filed. Namely, a motor-generator is mounted on a side of the rear wheel of the bicycle, and a control box and a battery are mounted under the main pipe of the bicycle, and a change-over switch and a change speed switch are mounted on the handle of the bicycle.

Accordingly, it is an object of the present invention to provide a bicycle in which charging is made via a motor-generator when pedaling on a downhill or level ground, and electric power of the battery is conveyed to the rear wheel via the motor-generator to rotate it, so that the bicycle can have driving force from the motor-generator that can rationally solve all the problems that the conventional bicycle and electric bicycle had.

In order to accomplish the foregoing objects, the present invention provides a bicycle deriving driving force by a motor-generator having a rotating plate of a nonmagnetic material having a plurality of radially fixed magnets, fixed plates of a nonmagnetic material which are placed on both sides of the rotating plate and have a plurality of horizontally wound coil units corresponding to the magnets, and a rotating axis which is mounted on the center of the rotating plate and at both ends of which are fixed the plates through the bearings, the bicycle comprising: a motor-generator which is mounted on the side of the rear wheel of the bicycle; a power transmission means including a driving pulley which is fixed on the shaft where the rear wheel of the bicycle is rotatably mounted, a driven pulley which is mounted on one end of the rotating axis mounted on the center of the rotating plate, and a belt which operatively connects the driving pulley and the driven pulley; a control box and a battery which are mounted on the bicycle and are connected with the coil units; and a change-over switch which is mounted on the handle of the bicycle and converts the motor-generator in such a way that it can be used selectively as a generator or a motor.

The present invention makes it possible to charge quickly and effectively via a motor-generator that is operated by the bicycle driving force on a downhill or level ground, and with charging made, the rotary force of the motor-generator is conveyed to the rear wheel to generate electric power, so that electromotive force is produced and stored by itself, and the driving force of the bicycle can be obtained by using the stored electric power. Therefore, it is possible to use the bicycle easily and conveniently for a long time, and it has an effect of much reduced leg fatigue even in the case of moving a long distance.

BEST MODE

Hereinafter, preferred embodiments of the present invention will be described in more detail through the following examples.

Prior to this, terms or words used in the specification and claims should not be construed as limited to a lexical meaning, and should be understood as appropriate notions by the inventor based on that he/she is able to define terms to describe his/her invention in the best way to be seen by others.

FIG. 1is an exploded perspective view showing major parts of a conventional motor-generator.

The motor-generator disclosed in Korean Patent Application No. 2009-035298 that the applicant of the present invention filed includes a rotating plate10on which a plurality of magnets11and11′ are radially attached and fixed plates20and20′ on which a plurality of coil units21and21′ are radially placed and horizontally wound. The fixed plates20and20′ are placed in separation at a predetermined interval on both sides of the rotating plate10. A rotating axis12is fitted on the center of the rotating plate10, and the fixed plates20and20′ are rotatably mounted on both ends of the rotating axis12by bearings.

Accordingly, when the rotating plate10is rotated by the power of pedaling, the electric charge having a predetermined polarity generated from the magnets11and11′ is applied to the coil units21and21′, and the electricity generated from the coil units21and21′ by the electric charge is stored in the battery by way of a transformer and rectifier diode. Therefore, this system can be used as a chargeable generator.

Conversely, when external electricity is applied to the coil units21and21′, the electric charge generated from the coil units21and21′ interfere with the polarity of the magnets11and11′ of the rotating plate10to generate attractive force and repulsive force between them. Therefore, it is possible to use the rotating plate10as a continuously rotating motor via alternating transfer supply of external electricity.

FIG. 2is a side view showing the overall construction of a bicycle according to the present invention, andFIG. 3is an enlarged rear view showing the rear wheel of the bicycle according to the present invention, andFIG. 4is a circuit diagram showing the electromotive means of the bicycle according to the present invention.

As described above, a motor-generator30having the rotating plate10and fixed plates20and20′ are mounted on the side of the rear wheel51of the bicycle50. A separate driving pulley53is fixed together on the shaft52where the rear wheel51of the bicycle50is rotatably installed. A separate driven pulley13is fixed on one end of the rotating axis12that is mounted on the center of the rotating plate10. In this state, by operatively connecting the driving pulley53and driven pulley13via the belt54, power transmission between the rotating body and rear wheel is made by these power transmission means.

In particular, by adjusting the rotation ratio of the driven pulley13and driving pulley53, electricity generation or electromotive efficiency can be improved. Namely, by forming the diameter of the driven pulley13to be small and the diameter of the driving pulley53to be large, the driven pulley13rotates more while the driving pulley53makes one rotation. Therefore, a larger quantity of electricity storage is possible during generation, and an increase of rotary force is possible during electromotive operation.

And it is preferable to use a timing belt for the belt54for more accurate transmission of rotary force. Also for the driven pulley13and driving pulley53that are operatively connected via the timing belt, it is preferable that they have sawteeth in a form corresponding to the timing belt. Any kind of construction that can transmit power, such as the timing belt54, driven pulley13and driving pulley53, can be used. For example, besides the structure of timing belt as described above, a power transmission structure with a chain and sprocket can also be used.

In the process of mounting a motor-generator30on one side of the rear wheel51of the bicycle50, the lower end of one fixed plate20is fastened directly to the shaft52of the rear wheel51, and the upper end of the fixed plate20is installed by using a separate support80that is fixed to the bicycle50. Accordingly, the motor-generator30can maintain a stable fixed state for the bicycle50, and a control box60and battery70connected to the motor-generator30can be mounted in the necessary portion of the bicycle50.

In addition, on the handle55of the bicycle50are mounted a change-over switch56for selective use of a motor or generator and a speed change switch57that can adjust the rotation velocity of the motor40in case the motor-generator30is used as a motor.

In the bicycle of the present invention having such a construction, storage of electricity is made by a transformer61and a rectifier diode62in the control box60, and the motor is driven by a polarity change-over unit63and variable speed unit66with a phase sensor64and phase delivery unit65.

Namely, as shown inFIG. 5, with the battery70sufficiently charged, the change-over switch56mounted on the handle of the bicycle50is operated to have the electricity of the battery70applied to the coil units21and21′ of the fixed plates20and20′, then the rotating plate10is forced to rotate by attractive force and repulsive force acting in polarity between the electric charges acting on coil units21and21′ and magnets11and11′.

At this time, the electricity of the battery70is supplied by repeatedly changing the polarity by the polarity change-over unit63, so that the rotating plate10can have rotary force of the same direction continuously. Also, the polarity change-over unit63is connected to the phase sensor64that detects the phase of magnets11and11′ and the phase delivery unit65that delivers the detected signal of the phase sensor64. Therefore, as the magnets11and11′ of the rotating plate10start rotating, the polarity of the electricity provided from the battery70is continuously changed to be supplied to the coil units21and21′. As a result, the rotating plate10is continuously rotated by the attractive force and repulsive force action on the magnets11and11′.

Especially, to the coil units21and21′ placed radially on the fixed plates20and20′ electricity is supplied selectively by a separate variable speed unit66. At this time, the rotation velocity and the rotary torque for the rotating plate10can be adjusted by supplying the electricity applied to the coil units21and21′ via the variable speed unit66in an individual or group mode.

Such a variable speed unit66can be controlled via the speed change switch57mounted on the handle55of the bicycle50. Namely, the rotary velocity and rotary force of the rotating plate10can be increased or decreased by changing the supply mode of the electricity applied to each of the coil units21and21′ whenever the speed change switch57is operated.

Such a rotation structure of the rotating plate10by the battery70is described in detail in the above-mentioned preceding patent application.

Therefore, as the rotating plate10is rotated by using the battery70as described above, the driven pulley13and the driving pulley53rotate via the timing belt, and the rotary force of the driving pulley53is directly transmitted to the rear wheel52, so that it can be rotated by rotary force.

So in the case of an uphill or level ground, it is possible to use a bicycle conveniently by operating the motor-generator30in such a way that it plays a role of a motor.

FIG. 6is a circuit diagram showing the state in which generation is made by the driving force in the bicycle according to the present invention. In the case of riding downhill or level ground, the user can charge the battery70as necessary.

Namely, riding is possible without pedaling and only with the weight of the user and the weight of the bicycle itself when going downhill. In such a case, the change-over switch56mounted on the handle55is operated to have the motor-generator30play a role of a generator.

Here, the change-over switch56can be operated by the user pressing it personally, or it can be configured in such a way that the change-over switch56is automatically operated when going downhill for automatic change-over from the function of motor to the function of generator, by mounting on the bicycle a change-over switch56of a type operating according to the angle with respect to the horizon.

As the function is changed to that of a generator, the rotary force of the rear wheel51is transmitted to the rotating plate10to rotate it by force, and then the magnets11and11′ of the rotating plate10affect the coil units21and21′ of the fixed plates20and20′ to generate an electric charge. As described above, the electric charge generated from the coil units21and21′ is rectified by way of the transformer61, and alternating current is converted to direct current by the rectifier diode62to have the battery70charged automatically.

In particular, since the above-described motor-generator30rotates in a free running mode in which interference resistance between the magnets11and11′ of the rotating plate10and the coil units21and21′ of the fixed plates20and20′ does not occur at all, the running power of the bicycle is not affected even while the above-described generation action is being carried out.

Thus, the bicycle of the present invention makes selective operation as a motor or a generator possible on terrain such as downhill or uphill, so long-time or long-distance riding through continuous charging are possible as well as convenient use of the bicycle.

Also, as shown inFIG. 7, the motor-generators30of the present invention can be mounted on both sides of the rear wheel51as well by using supports80. In this case, much higher electromotive force or generation efficiency can be obtained by the motor-generators30on both sides, so the role as an electromotive bicycle can be achieved more sufficiently.

Although the present invention has been described in connection with the exemplary embodiments illustrated in the drawings, it is only illustrative. It will be understood by those skilled in the art that various modifications and equivalents can be made to the present invention. Therefore, the true technical scope of the present invention should be defined by the appended claims.