ELEVATOR RESCUE SYSTEM

• US 20160280507A1
• Filed: 02/24/2016
• Published: 09/29/2016
• Est. Priority Date: 03/23/2015
• Status: Active Application

• Current Assignee: Kone Corporation
• Original Assignee: Kone Corporation
• Inventors: KATTAINEN, Ari, NAKARI, Arto
• Granted Patent: US 10,273,116 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B66B 1/32 effective on braking devices , e.g. acting on electrically controlled brakes brake control H02P, lift brakes per se B66B5/02
• CPC Class Codes: B66B 5/02 responsive to abnormal operating conditions
• CPC Class Codes: B66B 5/027 to permit passengers to leave an elevator car in case of failure, e.g. moving the car to a reference floor or unlocking the door
• CPC Class Codes: B66B 5/044 Mechanical overspeed governors

Abstract

The invention refers to an elevator rescue system (10) for moving an elevator car of an elevator in an emergency situation, which elevator includes an elevator motor acting on hoisting ropes by which the elevator car is suspended and/or moved, which elevator motor comprises at least one electro-mechanical brake (14a, 14b) and an encoder outputting a signal corresponding to its speed,

which system comprises

• • a back-up power source (36),
  • a jerk monitoring circuit (22) connected to the encoder and comprising a memory (28) for at least one first upper threshold value for the car acceleration and/or its derivation,
  • a brake feed circuit (16) which is controlled by the jerk monitoring circuit,
  • at least one release switch (24) which is connected to the jerk monitoring circuit and/or to the brake feed circuit,
    in which system the operation of the release switch activates the brake feed circuit to release the brake, and initiates the jerk monitoring circuit to compare the car acceleration and/or its derivation as derived from the encoder signal with the stored first upper threshold value, whereby it forwards a control signal to the brake feed circuit to initiate/stop braking depending on the comparison result.

Claims

1. Elevator rescue system for moving an elevator car of an elevator in an emergency situation, which elevator includes an elevator motor acting on hoisting ropes by which the elevator car is suspended and/or moved, which elevator motor comprises at least one electro-mechanical brake and an encoder outputting a signal corresponding to its speed, which system comprises

a back-up power source,

a jerk monitoring circuit connected to the encoder and comprising a memory for at least one first upper threshold value for the car acceleration and/or its time derivative,

a brake feed circuit which is controlled by the jerk monitoring circuit,

at least one release switch which is connected to the jerk monitoring circuit and/or to the brake feed circuit,

in which system the operation of the release switch activates the brake feed circuit to release the brake, and initiates the jerk monitoring circuit to compare the car acceleration and/or its derivation as derived from the encoder signal with the stored first upper threshold value, whereby it forwards a control signal to the brake feed circuit to initiate/stop braking depending on the comparison result.

2. System according to claim 1, comprising at least one car location indicator connected to the jerk monitoring circuit and/or to the brake feed circuit, whereby a stopping control signal is forwarded to the brake when the jerk monitoring circuit or the brake feed circuit receives a signal from the car location indicator, that the car has reached a floor area.

3. System according to claim 1 or 2, wherein the brake comprises

a spring means biasing the brake into a gripping state and

an electro-magnetic release means to push the brake into a release state against the force of the spring means.

4. System according to claim 1, wherein the brake feed circuit comprises a DC/DC voltage converter, which is connected to the backup power source.

5. System according to claim 1, wherein the backup-power source is a battery or an accumulator.

6. System according to claim 1, wherein the brake feed circuit comprises a semiconductor switch, particularly an IGBT or MOSFET etc., which is connected to an output of the brake feed circuit, whereby a control connector of the semiconductor switch is coupled to the jerk monitoring circuit.

7. System according to claim 1, wherein the operation of the release switch activates the jerk monitoring circuit to forward a control signal to the brake feed circuit to release the brake.

8. System according to claim 1, wherein the control signal is a binary signal which is “

high”

to release the brake and which is “

low”

to activate the brake.

9. System according to claim 1, wherein the power for the operation of the brake feed circuit and/or of the jerk monitoring circuit is obtained from the back-up power source.

10. System according to claim 1, wherein the car speed of the elevator is monitored by an overspeed governor.

11. System according to claim 1, comprising a dynamic braking circuit short-circuiting the windings of the elevator motor, which dynamic braking circuit is preferably powered by the back-up power source.

12. System according to claim 11, whereby solid state switches of an inverter of the motor drive are used for dynamic braking, whereby a dynamic braking control gets its operating supply voltage from a DC intermediate circuit of the inverter.

13. Elevator comprising a system according to claim 1.

14. Method for moving an elevator car of an elevator in an emergency situation, which elevator includes an elevator motor acting on hoisting ropes by which the elevator car is suspended and/or moved, which elevator motor comprises at least one electro-mechanical brake and an encoder outputting a signal corresponding to its speed, using

a back-up power source,

a brake feed circuit to operate the electro-mechanical brake,

at least one release switch to initiate a rescue operation, and

in which method the operation of the release switch activates the release of the brake to move the elevator car in the direction of a floor, whereby after operating the release switch the acceleration of the elevator car and/or its derivation are monitored and the brake is activated every time the acceleration and/or its derivation exceeds an upper threshold value.

15. Method according to claim 14, wherein at least one car location indicator is used to monitor the level of the elevator car with respect to the floor level to which the elevator car approaches, and that the car is moved in line with until the car location indicator indicates arrival of the elevator car in a floor area, whereafter current output to the brake is stopped.

16. Method according to claim 14 or 15, wherein after activation of the brake after exceeding the upper threshold value the brake is opened again after the car speed has dropped to a lower threshold value.

17. Method according to claim 14 wherein the operation of the release switch starts the jerk monitoring unit to control dynamic braking of the elevator motor via a dynamic braking circuit.

18. Method according to claim 14 whereby an overspeed governor is used to monitor the elevator car speed.

19. Method according to claim 14 using a system comprising:

a jerk monitoring circuit connected to the encoder and comprising a memory for at least one first upper threshold value for the car acceleration and/or its time derivative; and

a brake feed circuit which is controlled by the jerk monitoring circuit;

wherein the release switch is controlled by the jerk monitoring circuit;

in which system the operation of the release switch activates the brake feed circuit to release the brake, and initiates the jerk monitoring circuit to compare the car acceleration and/or its derivation as derived from the encoder signal with the stored first upper threshold value, whereby it forwards a control signal to the brake feed circuit to initiate/stop braking depending on the comparison result.