Retorque measuring apparatus
US4319494A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 17, 1980 |
| Grant date | Mar 16, 1982 |
| Priority date | — |
| Expiry date | Dec 17, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L1/225
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Apparatus for measuring the amount of previously applied torque to a fastener. A transducer is utilized to sense the amount of a subsequently applied torque to the fastener and provides an output signal representative of the applied torque. The torque is applied until further motion or breakaway of the fastener is obtained. Typically, the signal from the transducer increases until breakaway of the fastener is obtained and then the signal decreases momentarily to a valley before it again increases with further applied torque. In those instances where the particular fastener does not exhibit a well-defined valley torque signal, provision is made for detecting the value of the transducer torque signal upon breakaway. Preferably, circuitry is provided for artificially creating the valley when there is a change of slope in the torque signal above a given threshold level. This artificially created valley is detected by a negative peak detector whose output is generally closely associated with the amount of torque originally applied to the fastener.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.