Patent ID: 7353914

Claim:
A safety system for an elevator installation for transporting of persons/goods in a building, comprising: a shaft; at least two cages which are arranged above one another so as to move independently of one another in the shaft; a drive for each cage; at least one drive control for controlling the drives; cage position detecting sensors for detecting positions of each cage in the shaft; at least one safety control, the cage position detecting sensors being operative to transmit cage position data to the at least one safety control; shaft doors arranged to close accesses to the shaft; locks operatively arranged to lock the shaft doors; and lock setting detecting sensors operative to detect settings of the locks, the lock setting detecting sensors being further operative to transmit lock setting data to the safety control, the safety control being operative to ascertain from the cage position data and the lock setting data shaft region data having details with respect to shaft regions in which each cage is safely movable.