Patent ID: 7946393
Filing Date: 2011-05-24
Classification: B66B

Abstract:
1. Elevator unit with an elevator car movable in an elevator shaft, the elevator unit comprising: a braking device for slowing the elevator car; a catching device having catching elements for stopping the elevator car; a first sensor for generating electrical signals in cooperation with a first measuring strip, the electrical signals representing a speed of the elevator car; a second sensor for generating electrical signals representing the speed and an absolute position of the elevator car; a third sensor for generating electrical signals representing the speed and the absolute position of the elevator car; and an evaluation circuit including first and second channels, each channel electrically connected to the first, second and third sensors, each channel operable to evaluate the electrical signals generated by the third sensor and one of the first and second sensors to determine the absolute position and the speed of the elevator car, the evaluation circuit being operable to activate the braking device via a first output of the evaluation circuit if the speed of the elevator car exceeds a preset range at the absolute position and activate the catching device via a second output of the evaluation circuit if the absolute position and the speed of the elevator car continue to deviate from desired values after activation of the braking device, and the evaluation circuit being operable to continuously compare variables computed by the first and second channels.