Backup position signaling in an elevator
First Claim
1. An elevator comprising a car, a car controller, and position transducer connected to a car for providing distinct car position signals, a source of system power, the elevator being characterized by:
- position memory means for storing position signals from the transducer therefrom for retrieval by the controller after the controller is shut down and restarted;
a backup power supply;
first switch means for connecting the supply to the position memory means in response to a first control signal;
second switch means for connecting the power supply to the position sensor in response to a second control signal;
logic means for receiving a car position signal from the position transducer for sensing system power level and providing said first and second control signals when the level decreases below a reference level.
1 Assignment
0 Petitions
Accused Products
Abstract
An elevator has a car position transducer that provides an output signal indicating car location. A car controller causes that signal to be stored in a memory. The controller compares the stored signal with a current transducer output and stores the current signal when the difference between the two exceeds a preset amount. A detector senses the elevator system power level and connects a backup power supply to the memory and the transducer when there is a power loss. A car motion detector senses the transducer output and removes the backup power from the transducer when the car stops moving.
19 Citations
3 Claims
-
1. An elevator comprising a car, a car controller, and position transducer connected to a car for providing distinct car position signals, a source of system power, the elevator being characterized by:
-
position memory means for storing position signals from the transducer therefrom for retrieval by the controller after the controller is shut down and restarted; a backup power supply; first switch means for connecting the supply to the position memory means in response to a first control signal; second switch means for connecting the power supply to the position sensor in response to a second control signal; logic means for receiving a car position signal from the position transducer for sensing system power level and providing said first and second control signals when the level decreases below a reference level. - View Dependent Claims (2, 3)
-
Specification