Adjustment device for photographic enlarging or reproducing apparatus

摘要

A device for displacing a body along a guiding column which is particularly suitable for the projection head of an enlarging or reproducing apparatus. The device comprises in a conventional manner a guiding column and, on the body, a friction wheel which presses against the column and which is disposed on a shaft. The shaft of the friction wheel is mounted in the sleeve-like body which surrounds the column except in the vicinity of the friction wheel. The friction wheel is sub-divided into two wheel portions and means are provided for exerting a force upon the wheel portions along the axis of the friction wheel. These means act upon a guiding surface of the column disposed at an angle of up to 90 DEG with respect to the friction wheel axis.