Elevator

Abstract

An elevator and a method for testing an operating condition of two or more elevator car brakes are provided, each of the car brakes including an actuator to control the car brake and each of the car brakes mounted to elevator car and fitted to selectively engage against a guide rail of an elevator car to stop movement of an elevator car or to open to enable movement of an elevator car. The method includes an empty car is kept at a standstill by providing a driving force upwards with all the N movers mounted to the elevator car, and total current Lot of all N movers is determined. One of the car brakes is applied while the others are kept open. The driving current of each of the movers is gradually decreased, and movement of elevator car is observed. When movement of elevator car is detected, the driving current at the moment movement started is recorded, and the recorded current is compared to a reference value, and if the recorded current is higher than the reference value, safety measures with the elevator are performed.

1 . An elevator comprising:
 an elevator car; one or more guide rails to define path of movement of an elevator car; and   an electric linear motor comprising at least one linear stator designed to be located in a fixed correlation to an environment, and at least one mover designed for connection with an elevator car to be moved and co-acting with the stator to move the car, the electric linear motor comprising a stator beam supporting said at least one stator, the stator beam having at least one side face carrying ferromagnetic teeth of said stator spaced apart by a pitch, and the mover comprises at least one counter-face facing said side face of the stator beam, the motor further comprising electro-magnetic components being mounted to the mover and/or to the stator to provide propulsion force to the elevator car; elevator   two or more elevator car brakes mounted to an elevator car, each of the car brakes comprising an actuator to control the car brake and each of the car brakes being fitted to selectively engage against a guide rail of an elevator car to stop movement of an elevator car or to open to enable movement of an elevator car.   
     
     
         2 . The elevator according to  claim 1 , further comprising a backup-power supply and an emergency stop circuit, the emergency stop circuit being connected to a position and/or velocity and/or acceleration sensor of the elevator, and the emergency stop circuit being configured to adjust the energization of the electromagnetic components and/or the actuators of one or more car brakes depending on the signal of the above sensor. 
     
     
         3 . The elevator according to  claim 2 , wherein the backup-power supply is a battery. 
     
     
         4 . The elevator according to  claim 3 , further comprising a battery monitoring circuit for monitoring the functional status of the battery. 
     
     
         5 . The elevator according to  claim 2 , wherein the emergency stop circuit is configured to adjust the energization of the electromagnetic components and/or the actuators of one or more car brakes such that the car stops within a defined stopping distance. 
     
     
         6 . The elevator according to  claim 1 , wherein the elevator control comprises a brake test circuit configured to operate in a brake test mode wherein only one actuator is de-energized to apply elevator car brake when the car is not moving. 
     
     
         7 . The elevator according to  claim 1 , wherein associated with each car brake there is a load sensor, arranged between the car and the car brake to measure a total weight of car. 
     
     
         8 . A method for testing an operating condition of an elevator car brake in the elevator according to  claim 1 , the method comprising the succession of following steps:
 keeping an empty car at a standstill by providing a driving force upwards with the at least one mover mounted to the elevator car;   applying one of the car brakes while the others are kept open;   gradually decreasing the driving current of the at least one mover and observing movement of elevator car;   when movement of elevator car is detected, recording the driving current of the at least one mover at the moment movement started, and comparing the recorded current to a reference value; and   if the recorded current is higher than the reference value, performing safety measures with the elevator.   
     
     
         9 . A method for testing an operating condition of elevator car brake in an elevator according to  claim 1 , wherein associated with each of the car brakes there is a load sensor, arranged between the car and the car brake to measure a total weight of car, the method comprising the succession of following steps:
 applying one of the car brakes while the others are kept open;   keeping an empty car at a standstill by providing a driving force upwards with the at least one mover, such that the load sensor of the applied car brake indicates zero weight;   gradually decreasing the driving current of the at least one mover, and observing movement of elevator car;   when movement of elevator car is detected, recording the reading of the load sensor of the applied car brake at the moment movement started, and comparing the recorded reading to a reference value; and   if the recorded reading of the load sensor is lower than the reference value, performing safety measures with the elevator.   
     
     
         10 . The method according to  claim 8 , which wherein the brake test mode is performed when the car is stopping at a floor. 
     
     
         11 . The method according to  claim 8 , wherein the safety measures comprise at least one of the following steps:
 sending a log report with the energization when the car starts moving to a maintenance center;   sending a log report with the threshold value which the energization was compared to a maintenance center;   putting the elevator out of service; and   issuing a maintenance request.   
     
     
         12 . The elevator according to  claim 3 , wherein the emergency stop circuit is configured to adjust the energization of the electromagnetic components and/or the actuators of one or more car brakes such that the car stops within a defined stopping distance. 
     
     
         13 . The elevator according to  claim 4 , wherein the emergency stop circuit is configured to adjust the energization of the electromagnetic components and/or the actuators of one or more car brakes such that the car stops within a defined stopping distance. 
     
     
         14 . The elevator according to  claim 2 , wherein the elevator control comprises a brake test circuit configured to operate in a brake test mode wherein only one actuator is de-energized to apply elevator car brake when the car is not moving. 
     
     
         15 . The elevator according to  claim 3 , wherein the elevator control comprises a brake test circuit configured to operate in a brake test mode wherein only one actuator is de-energized to apply elevator car brake when the car is not moving. 
     
     
         16 . The elevator according to  claim 4 , wherein the elevator control comprises a brake test circuit configured to operate in a brake test mode wherein only one actuator is de-energized to apply elevator car brake when the car is not moving. 
     
     
         17 . The elevator according to  claim 5 , wherein the elevator control comprises a brake test circuit configured to operate in a brake test mode wherein only one actuator is de-energized to apply elevator car brake when the car is not moving. 
     
     
         18 . The elevator according to  claim 2 , wherein associated with each car brake there is a load sensor, arranged between the car and the car brake to measure total weight of car. 
     
     
         19 . The elevator according to  claim 3 , wherein associated with each car brake there is a load sensor, arranged between the car and the car brake to measure total weight of car. 
     
     
         20 . The elevator according to  claim 4 , wherein associated with each car brake there is a load sensor, arranged between the car and the car brake to measure total weight of car.