Transducer for indicating torque
US4281538A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 6, 1975 |
| Grant date | Aug 4, 1981 |
| Priority date | — |
| Expiry date | Oct 6, 1995 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB25B23/1456
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A pneumatic power tool having a torque sensing control system is disclosed which is capable of consistently applying a precise torque to a fastener so that uniform tightening of any number of fasteners can be obtained. A torsional strain responsive transducer is mounted internally in the tool body and includes a strain gauge network mounted on a torsionally resilient portion of one of the gear cases of the drive train of the tool, the gear case being subject to a reaction component of the torque being transmitted through the drive train. The strain gauge network provides a control signal which effects energization of a solenoid-actuated air shut-off valve in the handle of the tool to automatically terminate the operation of the tool when a predetermined torque is obtained at the output spindle. The control system permits adjustment of the torque output of the tool and provides a visual readout of such output.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.