| 摘要 |
An electrically driven optical instrument such as stereo-microscope is provided with a transfer shaft rotatably carrying a drive transmitting, transfer gear. An axial displacement of the transfer gear occurs in response to an external operation to move the transfer gear selectively to a first position in which it meshes with an output gear on a motor and a second position in which it meshes with a manually driven gear that is mounted on an externally exposed operating shaft, thus accomplishing a switching between an electrical drive and a manual drive.
|
