Zoom drive, especially for a microscope, has a design that minimizes friction forces therefore reducing the required torque so that drive motor loading is reduced and a compact motor can be used

摘要

Zoom drive comprises a motor drive unit (1) with a mounted threaded spindle (4) that is used to adjust the position of a lens group (8) mounted on a displacement element (10) that has a threaded segment that meshes with the spindle. An elastic coupling (3) is provided between the drive shaft (2) of the motor and the threaded spindle. This, the shape of a form element (11) for taking up the play and the threaded spindle bearings are designed to minimize friction forces.