Mechanism for raising and lowering doors - has displaceable rods with gearing for movement with minimum effort

摘要

The lift device to remove a door from its hinges, prevents damage to the hinges. It has fixed frame with a horizontal floor strip (1) mounted on rollers (3) and runs parallel to the door. A vertical rod (7) connected to the centre of the floor strip has a toothed rack (8) over part of its length. The lift carriage on which the door rests and which moves at right angles to the frame consists of a horizontal lever strip (5) parallel to the floor strip (1) and a tube (2) concentric with the upright rod (7). The lever strips (5) has a lifting bracket (6) each end which engages beneath the door whilst the lift carriage itself can be raised by a toothed gear (10) attached above the upper end of the tube (2) and which engages the toothed rack (8). The gear is operated by a crank handle (9).