Granted Patent B2

US 6,866,111 · App. 10/393,392 · Granted Mar 15, 2005

Abstract

Claims (38)

1. A system for proportionally assisting by a DC motor propulsion of a wheeled vehicle propelled by a user who provides a user effort, comprising:

detection and measurement means for detecting and measuring a flexion of a fixed shaft of a wheel of said vehicle on which said DC motor is secured and subjected to said user effort, said detection and measuring means being mounted on a flat vertical surface formed in said fixed shaft;

assistance level request means for requesting a level of assistance to be provided;

digitizing means for digitizing a signal obtained from said detection and measurement means;

effort calculation means to calculate, in real time, the user effort provided by said user using said digitized signal;

assistance level calculation means for calculating an appropriate assistance effort to be provided by a DC motor mounted on said wheel using a value of said user effort and a value of said level of assistance requested;

control means for controlling an assistance effort to be provided by said DC motor mounted on said shaft of said wheel and using a value of said appropriate assistance effort;

wherein said user effort and said level of assistance requested are used to proportionally assist propulsion of said vehicle by said DC motor.

2. A system as claimed in claim 1 , wherein said detection and measurement means is a strain gauge.

3. A system as claimed in claim 1 , wherein said wheel is said rear wheel of said wheeled vehicle.

4. A system as claimed in claim 1 , wherein said DC motor is powered by an electric battery.

5. A system as claimed in claim 1 , further comprising amplification means for amplifying said measured signal obtained from said detection and measurement means.

6. A system as claimed in claim 1 , further comprising filter means for a compensation circuit for compensating for any deviation of said measured signal by filtering out deviation in said signal.

7. A system as claimed in claim 1 , wherein a stator core of said motor is mounted on said fixed shaft, said motor having a rotor housing secured to said wheel for rotation about said stator core.

8. A system as claimed in claim 1 , wherein said flexion of said fixed shaft is horizontal with respect to ground on which said vehicle is used.

9. A system as claimed in claim 7 , further comprising a filter at an input of said amplification means.

10. A system as claimed in claim 1 , wherein said DC motor is a maintenance-free DC brushless motor.

11. A system as claimed in claim 1 , wherein there is further provided

amplification means for amplifying a measurement signal coming from said strain gauge;

a filter at an input of said amplification means;

an analog to digital converter at an output of said amplification means;

a digital processing circuit to digitize a signal at said output of said amplification means to compensate for any deviation of the said signal to calculate, in real time, the effort provided by the cyclist on gears secured to said motor and transferred to said fixed shaft and to control the assistance effort of the DC motor secured to the rear wheel of the bicycle to give a progressive assistance to the cyclist.

12. A method for proportionally assisting a propulsion of a wheeled vehicle propelled by a user who provides an user effort, comprising:

detecting and measuring a flexion of a fixed shaft of said vehicle subjected to said user effort by a detection and measuring means mounted on a flat vertical surface formed in said fixed shaft;

requesting a level of assistance to be provided;

digitizing a signal obtained from said detection and measuring means;

calculating, in real time, the user effort provided by said user using said digitized signal;

calculating an appropriate assistance effort to be provided by a DC motor mounted on said wheel using a value of said user effort and a value of said level of assistance requested;

controlling an assistance effort to be provided by said DC motor using a value of said appropriate assistance effort;

wherein said user effort and said level of assistance requested are used to proportionally assist propulsion of said vehicle by said DC motor.

13. A method as claimed in claim 12 , further comprising amplifying said measured signal obtained from said detection and measuring means which is a strain gauge providing signals representative of micro deformations in said flat surface.

14. A method as claimed in claim 12 , further comprising compensating for any deviation of said measured signal by filtering out deviation in said signal.

15. A method as claimed in claim 13 , further comprising filtering said measured signal prior to said amplifying.

16. A method as claimed in claim 13 , further comprising

amplifying said measured signal;

filtering said measured signal prior to amplifying;

converting said measured signal from analog to digital after said amplifying;

digitizing the amplified signal to compensate for any deviation of the said signal to calculate, in real time, the effort provided by the cyclist and transmitted to said fixed shaft whereby to control the assistance effort of the DC motor on the rear wheel of the bicycle to give a progressive assistance to the cyclist.

Assignments (13)