Housing construction for a power tool
US4043222A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 6, 1975 |
| Grant date | Aug 23, 1977 |
| Priority date | — |
| Expiry date | Oct 6, 1995 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T74/2186
- 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. Because of its fast action, the solenoid-actuated shut-off valve substantially eliminates reaction torque at the handle of the tool and the components thereof are compactly arranged. The sound level of the exhaust air from the pneumatic motor is attenuated by a tortuous flow p…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.