Torque responsive speed shifting mechanism for power tool
US3960035A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 1, 1974 |
| Grant date | Jun 1, 1976 |
| Priority date | — |
| Expiry date | Nov 1, 1994 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB25B23/145
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A speed shifting mechanism for a pneumatic wrench or nutsetter comprises a planetary gear arrangement in the drive mechanism of the wrench in which the planet gear carrier is connected to the driver clutch member of a torque responsive clutch and the planetary ring gear is mounted in a one way clutch to provide for unidirectional rotation of the ring gear. The torque responsive clutch is of the sloping tooth type and the driving clutch member is connected to a piston having opposing faces and fitted in the tool housing to form opposed fluid chambers. Pressure fluid is admitted to one of the chambers at a controlled pressure to act on the piston for holding the clutch in the engaged condition. Movement of the driving clutch member at torque causes pressure fluid at the controlled pressure to be vented and the opposite chamber to become pressurized thereby acting on the clutch to disengage and enable the planetary gear arrangement to become operative to reduce the output speed of the wrench.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.