Method and device for measuring a torque exerted on a part subjected to torque and bending loads
AssigneeNewtech Mecatronic Inc.
InventorGérard Faesch
Life of this patent
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Abstract
The invention concerns a method and a device for measuring a torque. The measuring method is characterized in that it consists in fixing on said part (1) at least two identical sensors (2) for measuring deformation, directly mounted between two separate anchoring points (A, B) and positioned on two curves (a) of the part (1) sloping at an angle a relative to the part (1) axis. Said sensors are designed to deliver electric signals based on modifications in distance between their respective anchoring points generated by said deformation.
Claims10
Method for measuring at least one component of a force tensor applied to a part (1), having an axis of symmetry and defined as follows in a trigonometric coordinate system:
- Fx Fy Fz
- Mx My Mz,
- wherein Fx and Fz are bending forces in an X and Z direction having corresponding moments Mx and Mz and My is a torsion moment associated with force Fy. the method requiring affixing at least two identical deformation measurement sensors (2) to said part (1), each being engaged between two distinct anchoring points (A, B) using fastening members (3) designed to transmit to said sensors (2) deformations of said part (1), a deformation of said fastening members (3) being negligible with respect to that of said part, said sensors (2) being designed to produce an electric signals as a function of a change in distance between said respective anchoring points (A, B) caused by said deformations;
- electrically conditioning signals from said sensors (2), said conditioning depending on said sensors (2);
- and combining said signals to deduct a value of said force tensor component, characterized in that the two distinct anchoring points (A, B) of each sensor (2) are placed on a surface of the part (1), such that the two lines (a) passing respectively through the two distinct anchoring points (A, B) of each sensor, carried to the surface of the part are substantially parallel and form a line parallel to the axis of symmetry of the part going through one of said anchoring points, forming an angle α greater than 0 degrees and smaller than 90 degrees.
A device for measuring at least one component of a force tensor applied to a part (1) having an axis of symmetry and defined as follows in a trigonometric coordinate system:
- Fx Fy Fz
- Mx My Mz
- wherein Fx and Fz are bending forces in an X and Z direction having corresponding moments Mx and Mz and My is a torsion moment associated with force Fy, capable of the implementation of a measurement method, said device comprising at least two identical deformation measurement sensors (2), each being mounted between two distinct anchoring points (A, B) and fixed to said part (1) using fastening members (3) designed to transmit to said sensors (2) deformations of said part (1), said sensors (2) being designed to produce electric signals as a function of changes in a distance between said respective anchoring points (A, B) generated by said deformations, an electronic circuit comprising an electronic signal conditioner at the output of said sensors (2), said signal conditioner being specifically associated with said sensors (2), and a calculator capable of integrating said signals in order to deduct a value of said force tensor component, each sensor (2) comprising two contacts (21) spaced apart (1) by an interval equivalent to said distance between said anchoring points (A, B) and a pretensioned blade (22) fixed at its extremities in said contacts (21) and having at least a sensible (22′) element thereon, characterized in that at least one of said contacts (21) comprises regulation means designed to adjust the pretension on said blade (22).
Dependencies are inferred from the claim text.