Cordless powered ratchet wrench
US4974475A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 19, 1989 |
| Grant date | Dec 4, 1990 |
| Priority date | — |
| Expiry date | Jul 19, 2009 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB25B21/00
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A cordless powered ratchet wrench includes a ratchet actuator that selects a direction of rotation of an output shaft that is adapted to hold rotating tools for use. The ratchet actuator also serves as a ratcheting stop to permit a limited amount of ratcheting motion for manual tightening or loosening of a nut, bolt or the like. A lost-motion drive transmits power from a battery to the output shaft while permitting nearly two full circles of ratcheting rotation. An external pushbutton operates internal switches to connect a rechargeable battery in a desired direction, and also functions as an interlock to prevent reversal of the direction in which torque is applied while the pushbutton is engaged. The ratchet actuator that selects a desired direction of rotation also functions to provide a positive driving surface for manual exertion of torque by an operator and as a ratchet to permit rotation in the opposite direction when the wrench is ratcheting, and it operates a switch to select a direction of powered motion. Exposed terminals prepare the wrench to be inserted into a charger for recharging the battery.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.