Method and apparatus for measuring friction torque
US5505078A · kind A · utility
Inventor
Key dates
| Filing date | Mar 30, 1995 |
| Grant date | Apr 9, 1996 |
| Priority date | — |
| Expiry date | Mar 30, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01M15/042
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Friction torque of a motor undergoing testing is measured by supporting an electrical motor on a test fixture and connecting a torque measuring device to its output shaft. The motor shaft is rotated in the reverse direction and while the motor shaft is freely rotating, power is applied to the motor and two torque measurements are taken to determine friction torque. The first is while the motor is still rotating in the reverse direction, and the second is taken from zero rpm to approximately 50 rpm. In both cases, the torque is measured while the motor shaft is near zero rpm, thus representing locked rotor torque. Half the difference between these two torque measurements will yield the value for friction torque. Motor torque is continued to be measured while the motor is accelerated to its maximum speed, and the value of this measured torque can then be adjusted by the value of the friction torque to provide a measurement of the actual torque of the motor being tested.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.