Electric motor driven screw driving or drilling tool device with planetary gear
US7537540B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 13, 2006 |
| Grant date | May 26, 2009 |
| Priority date | — |
| Expiry date | Nov 28, 2027 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H35/10
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
An electric motor-driven screw driving or drilling tool device with a planetary gear, comprising a ring gear and planet wheels mating with the ring gear, wherein the ring gear can be locked and fixed relative to the housing via locking bodies which are pretensioned by springs in a radially inward direction, the locking bodies being radially outwardly displaceable when a switch-off torque has been exceeded, such that the ring gear can be rotated relative to the housing, and the drive shaft is no longer driven. In order to improve the ease of operation of the device and reduce its size, the invention proposes leaf springs which extend in the peripheral direction of the ring gear, whose lever arm lengths can be adjusted in a peripheral direction to generate different bending forces acting on a respective locking body.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.