| 摘要 |
The arrangement comprises an installation platform arranged to be movable upwards and downwards in a first direction (S1) in the elevator shaft (20), two laser transmitters (210, 220) arranged at a bottom (12) of the elevator shaft (20), each of said two laser transmitters (210, 220) producing a vertical upwards directed laser plane (LP1, LP2) in the elevator shaft (20), said laser planes (LP1, LP2) being perpendicular to each other, at least four primary light sensitive detectors (310, 320, 330, 340) are attached to the installation platform (100) so that they are visible to the laser transmitters (210, 220), each of the primary light sensitive detectors (310, 320, 330, 340) being positioned on a respective side of a rectangle. The position of the installation platform (100) in relation to the elevator shaft (20) can be measured from the hitting points of the laser planes (LP1, LP2) on the primary light sensitive detectors (310, 320, 330, 340). |
