Sensor for measuring the torque of a drive shaft
View Patent ↗Disclosed is an assembly formed by a drive shaft for a vehicle and a sensor for measuring the value of a torque applied to the shaft, the sensor including a unit for generating a magnetic field and an arrangement formed by a first coil, a second coil, a third coil and a fourth coil arranged side-by-side between a first toothed wheel of the shaft and a second toothed wheel of the shaft, parallel to the first toothed wheel and to the second toothed wheel, arranged to be immersed in the magnetic field, the overall length of the first coil, of the second coil, of the third coil and of the fourth coil being equal to the period of the first toothed wheel and of the second toothed wheel.
1. An assembly formed by a drive shaft ( 10 ) for a vehicle and a sensor ( 20 ) for measuring the value of a torque applied to said drive shaft ( 10 ),
said drive shaft ( 10 ) comprising:
a first cylindrical portion ( 12 ) of a first diameter (D 1 ),
a second cylindrical portion ( 14 ) of a second diameter (D 2 ),
an intermediate torsion portion ( 16 ) linking the first portion ( 12 ) and the second portion ( 14 ) and with a section dimension less than the first diameter (D 1 ) and the second diameter (D 2 ) in order to concentrate a torsion generated by a torque applied to the shaft ( 10 ),
a first toothed wheel ( 13 ) mounted coaxially on the first portion ( 12 ), comprising, on its periphery, a plurality of teeth ( 18 - 1 ) alternating with tooth spaces and with a period (P) that corresponds to the length of the circular arc defined by a consecutive tooth ( 18 - 1 ) and tooth space ( 19 - 1 ) measured at the periphery of said tooth ( 18 - 1 ),
a second toothed wheel ( 15 ), identical to the first toothed wheel ( 13 ), mounted coaxially on the second portion ( 14 ) parallel to the first toothed wheel ( 13 ),
said sensor ( 20 ) comprising means for generating a magnetic field and an arrangement ( 26 ) formed by a first coil ( 26 - 1 ), a second coil ( 26 - 2 ), a third coil ( 26 - 3 ) and a fourth coil ( 26 - 4 ) arranged side-by-side between the first toothed wheel ( 13 ) and the second toothed wheel ( 15 ), parallel to said first toothed wheel ( 13 ) and to said second toothed wheel ( 15 ), said arrangement ( 26 ) being arranged to be immersed in said magnetic field and configured such that the overall length of the first coil ( 26 - 1 ), of the second coil ( 26 - 2 ), of the third coil ( 26 - 3 ) and of the fourth coil ( 26 - 4 ) is equal to the period (P) of the first toothed wheel ( 13 ) and of the second toothed wheel ( 15 ).
2. The assembly as claimed in claim 1 , in which the arrangement ( 26 ) takes the form of an annular sector arranged between the first toothed wheel ( 13 ) and the second toothed wheel ( 15 ), parallel to said first toothed wheel ( 13 ) and to said second toothed wheel ( 15 ).
3. The assembly as claimed in claim 2 , in which the annular sector is defined by an outer radius (R 1 ) and an inner radius (R 2 ), less than the outer radius (R 1 ), and is arranged facing the teeth ( 18 - 1 , 18 - 2 ) of the first toothed wheel ( 13 ) and of the second toothed wheel ( 15 ) such that the length (L) of the circular arc of the sector defined by its outer radius (R 1 ) corresponds to the period (P) of the first toothed wheel ( 13 ) and of the second toothed wheel ( 15 ).
4. The assembly as claimed in claim 3 , in which the first toothed wheel ( 13 ) and the second toothed wheel ( 15 ) each comprise a first reference tooth ( 18 - 1 A, 18 - 2 A), the first reference tooth ( 18 - 1 A) of the first toothed wheel ( 13 ) and the first reference tooth ( 18 - 2 A) of the second toothed wheel ( 15 ) are both facing the first coil ( 26 - 1 ) over a portion of length (al) that is non-zero and less than the period (P) of the first toothed wheel ( 13 ) and of the second toothed wheel ( 15 ) so as to define an initial position corresponding to an absence of torsion of the shaft ( 10 ).
5. A vehicle comprising an assembly formed by a drive shaft ( 10 ) for a vehicle and a sensor ( 20 ) for measuring the value of a torque applied to said shaft ( 10 ) as claimed in claim 4 .
6. A method for determining a torque applied to a drive shaft ( 10 ) of a vehicle, said method being implemented by an assembly as claimed in claim 4 , the first coil ( 26 - 1 ), the second coil ( 26 - 2 ), the third coil ( 26 - 3 ) and the fourth coil ( 26 - 4 ) each defining at their terminals, respectively, a first voltage (V 1 ), a second voltage (V 2 ), a third voltage (V 3 ) and a fourth voltage (V 4 ), said method comprising:
a step of torsion of the shaft ( 10 ) at its intermediate portion ( 16 ),
a step of measurement of the first voltage (V 1 ), of the second voltage (V 2 ), of the third voltage (V 3 ) and of the fourth voltage (V 4 ),
a step of calculation of the sum of the absolute value of the difference between the first voltage (V 1 ) and the third voltage (V 3 ) and the absolute value of the difference between the second voltage (V 2 ) and the fourth voltage (V 4 ),
a step of comparison of the calculated sum with a predetermined value corresponding to an absence of torsion of the shaft ( 10 ) so as to determine the value of the torque applied to the shaft ( 10 ).
7. A vehicle comprising an assembly formed by a drive shaft ( 10 ) for a vehicle and a sensor ( 20 ) for measuring the value of a torque applied to said shaft ( 10 ) as claimed in claim 3 .
8. A method for determining a torque applied to a drive shaft ( 10 ) of a vehicle, said method being implemented by an assembly as claimed in claim 3 , the first coil ( 26 - 1 ), the second coil ( 26 - 2 ), the third coil ( 26 - 3 ) and the fourth coil ( 26 - 4 ) each defining at their terminals, respectively, a first voltage (V 1 ), a second voltage (V 2 ), a third voltage (V 3 ) and a fourth voltage (V 4 ), said method comprising:
a step of torsion of the shaft ( 10 ) at its intermediate portion ( 16 ),
a step of measurement of the first voltage (V 1 ), of the second voltage (V 2 ), of the third voltage (V 3 ) and of the fourth voltage (V 4 ),
a step of calculation of the sum of the absolute value of the difference between the first voltage (V 1 ) and the third voltage (V 3 ) and the absolute value of the difference between the second voltage (V 2 ) and the fourth voltage (V 4 ),
a step of comparison of the calculated sum with a predetermined value corresponding to an absence of torsion of the shaft ( 10 ) so as to determine the value of the torque applied to the shaft ( 10 ).
9. The assembly as claimed in claim 2 , in which the first toothed wheel ( 13 ) and the second toothed wheel ( 15 ) each comprise a first reference tooth ( 18 - 1 A, 18 - 2 A), the first reference tooth ( 18 - 1 A) of the first toothed wheel ( 13 ) and the first reference tooth ( 18 - 2 A) of the second toothed wheel ( 15 ) are both facing the first coil ( 26 - 1 ) over a portion of length (al) that is non-zero and less than the period (P) of the first toothed wheel ( 13 ) and of the second toothed wheel ( 15 ) so as to define an initial position corresponding to an absence of torsion of the shaft ( 10 ).
10. A vehicle comprising an assembly formed by a drive shaft ( 10 ) for a vehicle and a sensor ( 20 ) for measuring the value of a torque applied to said shaft ( 10 ) as claimed in claim 9 .
11. A method for determining a torque applied to a drive shaft ( 10 ) of a vehicle, said method being implemented by an assembly as claimed in claim 9 , the first coil ( 26 - 1 ), the second coil ( 26 - 2 ), the third coil ( 26 - 3 ) and the fourth coil ( 26 - 4 ) each defining at their terminals, respectively, a first voltage (V 1 ), a second voltage (V 2 ), a third voltage (V 3 ) and a fourth voltage (V 4 ), said method comprising:
a step of torsion of the shaft ( 10 ) at its intermediate portion ( 16 ),
a step of measurement of the first voltage (V 1 ), of the second voltage (V 2 ), of the third voltage (V 3 ) and of the fourth voltage (V 4 ),
a step of calculation of the sum of the absolute value of the difference between the first voltage (V 1 ) and the third voltage (V 3 ) and the absolute value of the difference between the second voltage (V 2 ) and the fourth voltage (V 4 ),
a step of comparison of the calculated sum with a predetermined value corresponding to an absence of torsion of the shaft ( 10 ) so as to determine the value of the torque applied to the shaft ( 10 ).
12. A vehicle comprising an assembly formed by a drive shaft ( 10 ) for a vehicle and a sensor ( 20 ) for measuring the value of a torque applied to said shaft ( 10 ) as claimed in claim 2 .
13. A method for determining a torque applied to a drive shaft ( 10 ) of a vehicle, said method being implemented by an assembly as claimed in claim 2 , the first coil ( 26 - 1 ), the second coil ( 26 - 2 ), the third coil ( 26 - 3 ) and the fourth coil ( 26 - 4 ) each defining at their terminals, respectively, a first voltage (V 1 ), a second voltage (V 2 ), a third voltage (V 3 ) and a fourth voltage (V 4 ), said method comprising:
a step of torsion of the shaft ( 10 ) at its intermediate portion ( 16 ),
a step of measurement of the first voltage (V 1 ), of the second voltage (V 2 ), of the third voltage (V 3 ) and of the fourth voltage (V 4 ),
a step of calculation of the sum of the absolute value of the difference between the first voltage (V 1 ) and the third voltage (V 3 ) and the absolute value of the difference between the second voltage (V 2 ) and the fourth voltage (V 4 ),
a step of comparison of the calculated sum with a predetermined value corresponding to an absence of torsion of the shaft ( 10 ) so as to determine the value of the torque applied to the shaft ( 10 ).
14. The assembly as claimed in claim 1 , in which the first toothed wheel ( 13 ) and the second toothed wheel ( 15 ) each comprise a first reference tooth ( 18 - 1 A, 18 - 2 A), the first reference tooth ( 18 - 1 A) of the first toothed wheel ( 13 ) and the first reference tooth ( 18 - 2 A) of the second toothed wheel ( 15 ) are both facing the first coil ( 26 - 1 ) over a portion of length (al) that is non-zero and less than the period (P) of the first toothed wheel ( 13 ) and of the second toothed wheel ( 15 ) so as to define an initial position corresponding to an absence of torsion of the shaft ( 10 ).
15. A vehicle comprising an assembly formed by a drive shaft ( 10 ) for a vehicle and a sensor ( 20 ) for measuring the value of a torque applied to said shaft ( 10 ) as claimed in claim 14 .
16. A method for determining a torque applied to a drive shaft ( 10 ) of a vehicle, said method being implemented by an assembly as claimed in claim 14 , the first coil ( 26 - 1 ), the second coil ( 26 - 2 ), the third coil ( 26 - 3 ) and the fourth coil ( 26 - 4 ) each defining at their terminals, respectively, a first voltage (V 1 ), a second voltage (V 2 ), a third voltage (V 3 ) and a fourth voltage (V 4 ), said method comprising:
a step of torsion of the shaft ( 10 ) at its intermediate portion ( 16 ),
a step of measurement of the first voltage (V 1 ), of the second voltage (V 2 ), of the third voltage (V 3 ) and of the fourth voltage (V 4 ),
a step of calculation of the sum of the absolute value of the difference between the first voltage (V 1 ) and the third voltage (V 3 ) and the absolute value of the difference between the second voltage (V 2 ) and the fourth voltage (V 4 ),
a step of comparison of the calculated sum with a predetermined value corresponding to an absence of torsion of the shaft ( 10 ) so as to determine the value of the torque applied to the shaft ( 10 ).
17. A vehicle comprising an assembly formed by a drive shaft ( 10 ) for a vehicle and a sensor ( 20 ) for measuring the value of a torque applied to said shaft ( 10 ) as claimed in claim 1 .
18. A method for determining a torque applied to a drive shaft ( 10 ) of a vehicle, said method being implemented by an assembly as claimed in claim 1 , the first coil ( 26 - 1 ), the second coil ( 26 - 2 ), the third coil ( 26 - 3 ) and the fourth coil ( 26 - 4 ) each defining at their terminals, respectively, a first voltage (V 1 ), a second voltage (V 2 ), a third voltage (V 3 ) and a fourth voltage (V 4 ), said method comprising:
a step of torsion of the shaft ( 10 ) at its intermediate portion ( 16 ),
a step of measurement of the first voltage (V 1 ), of the second voltage (V 2 ), of the third voltage (V 3 ) and of the fourth voltage (V 4 ),
a step of calculation of the sum of the absolute value of the difference between the first voltage (V 1 ) and the third voltage (V 3 ) and the absolute value of the difference between the second voltage (V 2 ) and the fourth voltage (V 4 ),
a step of comparison of the calculated sum with a predetermined value corresponding to an absence of torsion of the shaft ( 10 ) so as to determine the value of the torque applied to the shaft ( 10 ).