Slide projector for teaching purposes - is mounted on hollow column with rack teeth on one side

摘要

The arm carrying the projector has a T shaped end which can be inserted and locked after the arm rotation, so that it cannot be withdrawn through the front. Its own weight and that of the projector produce a torque locking the arm in the column rack teeth. After unlocking, the arm can be easily moved up and down, and then locked in the required position. In an embodiment, the column (9) is held on a platform. The projector (6) is mounted on the arm (7). The slides (5) are brought into the projector by a sliding frame (3). The projector (6) can be swung round for projection onto the wall.