Patent ID: 7448471
Filing Date: 2008-11-11
Classification: B66B

Abstract:
1. Elevator installation comprising at least one car, which can be made to travel in a shaft along a traveling path and has a safety gear, wherein a control unit, a drive and a brake are associated with the car and further comprising a safety device with a speed determining unit for determining the current speed of the at least one car, a distance determining unit for determining the actual distance of the at least one car from an obstacle, another car or an end of the shaft, and a determining unit for determining a critical distance and a minimum distance, which are dependent on the speed of the at least one car, it being possible by means of the safety device to trigger an emergency stop of the at least one car if the actual distance is less than the critical distance, and it being possible to trigger the safety gear of the at least one car if the actual distance is less than the minimum distance, the movement of the car when an emergency stop is properly performed following an emergency stop traveling curve, which represents the variation in speed of the car that is to be expected when the emergency stop is triggered, in dependence on the distance covered by the car, and the movement of the car when the safety gear is functioning properly following a safety gear traveling curve, which represents the variation in speed of the car that is to be expected when the safety gear is triggered, in dependence on the distance covered by the car, wherein it is possible by means of the determining unit to determine the critical distance in accordance with a prescribable emergency stop triggering curve and the minimum distance in accordance with a prescribable safety gear triggering curve, the safety gear triggering curve not touching the emergency stop traveling curve, and wherein it is possible to trigger the safety gear even before the car has reached the location with which the speed of zero is associated according to the emergency stop traveling curve.