Torquemeter with improved accuracy and method of use

Patent metadata

Field	Value
Publication number	US-9752942-B2
Application number	US-201414897129-A
Country	US
Kind code	B2
Filing date	Jun 27, 2014
Priority date	Jun 28, 2013
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

A non-contacting torquemeter capable of measuring torque in a rotating shaft with improved accuracy in the presence of relative motion between a rotating shaft and a transducer assembly is provided. The non-contacting torquemeter has improved robustness and reliability, and is able to self-calibrate. The non-contacting torquemeter is able to provide accurate torque measurements using a single transducer assembly positioned at a single azimuthal position on a rotating shaft.

First claim

What is claimed is:

1. A non-contacting torquemeter comprising:
a torque wheel assembly configured for coupling to a first portion of a rotating shaft for rotation with the rotating shaft;
a plurality of dynamic target teeth configured for coupling to a second portion of the rotating shaft for rotation with the rotating shaft, wherein the plurality of dynamic target teeth are configured to deflect with respect to the torque wheel assembly as a function of a torque applied to the rotating shaft;
a transducer assembly including at least one sensor separated from the torque wheel assembly by a gap and configured to measure a position and speed of the torque wheel assembly and the plurality of dynamic target teeth, wherein the at least one sensor further comprises:
a first sensor separated from the torque wheel assembly by a first gap and configured to measure a position and speed of the dynamic target teeth relative to the torque wheel assembly;
a second sensor separated from the torque wheel assembly by a second gap and configured to measure a position and speed of a reference portion of the torque wheel assembly; and

a processing unit in communication with the transducer assembly and configured to determine the torque applied to the rotating shaft based on the position and speed measured by the transducer assembly.

2. The non-contacting torquemeter of claim 1 , wherein the torque wheel assembly comprises:
a first torque wheel having a plurality of first recessed sections in an outer edge of the first torque wheel, the plurality of first recessed sections being spaced about the perimeter of the first torque wheel;
a second torque wheel having a plurality of second recessed sections in an outer edge of the second torque wheel, the plurality of second recessed sections being spaced about the perimeter of the second torque wheel; and
a plurality of reference target teeth each positioned within one of the plurality of second recessed sections.

3. The non-contacting torquemeter of claim 2 , wherein each of the plurality of dynamic target teeth are aligned within one of the plurality of first recessed sections in the first torque wheel.

4. The non-contacting torquemeter of claim 2 , wherein the first torque wheel, the second torque wheel, and the plurality of reference target teeth are integrated together as a single component configured for rotation with the rotating shaft.

5. The non-contacting torquemeter of claim 2 , wherein the first torque wheel comprises a first substantially disc-shaped element configured to be arranged substantially coaxially with the rotating shaft; and wherein the second torque wheel comprises a second substantially disc-shaped element configured to be arranged substantially coaxially with the rotating shaft and axially spaced from the first torque wheel.

6. The non-contacting torquemeter of claim 1 , wherein the at least one sensor comprises at least one variable reluctance sensor.

7. The non-contacting torquemeter of claim 1 , wherein the at least one sensor are substantially encapsulated within a housing.

8. The non-contacting torquemeter of claim 1 , comprising at least one resistance temperature detector in communication with the processing unit and positioned to measure a temperature at or near the transducer assembly.

9. A non-contacting torquemeter comprising:
a shaft rotatable about an axis;
a torque wheel assembly configured for coupling to a first portion of the shaft for rotation with the shaft, the torque wheel assembly comprising;
a first torque wheel having a plurality of first recessed sections in an outer edge of the first torque wheel, the plurality of first recessed sections being spaced about the perimeter of the first torque wheel:
a second torque wheel having a plurality of second recessed sections in an outer edge of the second torque wheel, the plurality of second recessed sections being spaced about the perimeter of the second torque wheel; and
a plurality of reference target teeth each positioned within one of the plurality of second recessed sections;

a plurality of dynamic target teeth coupled to a second portion of the shaft for rotation with the shaft, wherein each of the plurality of dynamic target teeth are aligned within one of the plurality of first recessed sections in the first torque wheel, and wherein the plurality of dynamic target teeth are configured to deflect with respect to the first torque wheel as a function of a torque applied to the rotating shaft;
a transducer assembly including at least one sensor separated from one of the first torque wheel or the second torque wheel by a gap and configured to measure a position and speed of the one of the first torque wheel and plurality of dynamic target teeth or the second torque wheel and plurality of reference target teeth;
a processing unit in communication with the transducer assembly and configured to determine the torque applied to the shaft based on the position and speed measured by the transducer assembly.
at least one resistance temperature detector in communication with the processing unit and positioned to measure a temperature at or near the transducer assembly.

10. The non-contacting torquemeter of claim 9 , wherein the at least one sensor comprises at least one variable reluctance sensor.

11. The non-contacting torquemeter of claim 9 , wherein the at least one sensor comprises:
a first sensor separated from the first torque wheel by a first gap and configured to measure a position and speed of the dynamic target teeth relative to the first torque wheel; and
a second sensor separated from the second torque wheel by a second gap and configured to measure a position and speed of the reference target teeth relative to the second torque wheel.

12. A method for measuring a torque on a rotating shaft, the method comprising:
measuring a position of a dynamic target relative to a torque wheel assembly, wherein the torque wheel assembly is coupled to a first portion of a rotating shaft for rotation with the rotating shaft, wherein the dynamic target is coupled to a second portion of the rotating shaft for rotation with the rotating shaft, and wherein the dynamic target is configured to deflect with respect to the torque wheel assembly as a function of a torque applied to the rotating shaft;
measuring a position of a reference target that is fixed in rotation with respect to the torque wheel assembly;
comparing the position of the dynamic target relative to the torque wheel assembly to the position of the reference target relative to the torque wheel assembly; and
determining a torque applied to the rotating shaft based on a difference between the position of the dynamic target relative to the torque wheel assembly to the position of the reference target relative to the torque wheel assembly.

13. The method of claim 12 , wherein measuring a position of a dynamic target relative to a torque wheel assembly comprises receiving an input from a first sensor positioned proximal to the torque wheel assembly; and wherein measuring a position of a reference target relative to the torque wheel assembly comprises receiving an input from a second sensor positioned proximal to the torque wheel assembly.

14. The method of claim 13 , wherein the first sensor comprises a first variable reluctance sensor, and receiving an input from a first sensor comprises receiving a first timing between logical triggers associated with a voltage response from the first variable reluctance sensor; and wherein the second sensor comprises a second variable reluctance sensor, and receiving an input from a second sensor comprises receiving

Assignees

• Lord Corp

Inventors

• Jolly Mark R
• Altieri Russell E
• Allred Charles J
• Hamel Michael
• Southward Stephen C

Classifications

• G01L3/101

  involving magnetic or electromagnetic means · CPC title

• G01L3/109

  involving measuring phase difference of two signals or pulse trains · CPC title

• G01L25/003 Primary

  for measuring torque · CPC title

• G01L3/10 Primary

  involving electric or magnetic means for indicating · CPC title