ELEVATOR SYSTEM

• US 20110278099A1
• Filed: 07/22/2011
• Published: 11/17/2011
• Est. Priority Date: 03/05/2009
• Status: Active Grant

• Current Assignee: Kone Corporation
• Original Assignee: Kone Corporation
• Inventors: KATTAINEN, Ari, LAAKSONHEIMO, Jyrki
• Granted Patent: US 8,235,180 B2
• Time in Patent Office: Days
• US Class Current: 187/288
• 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 5/06 electrical

Abstract

An elevator system and a brake control circuit include a first switch that controls the electricity supply of the winding of the brake, which switch is connected in a controlled manner with the control of the electricity supply of the winding of the brake, and thus the braking function is controlled.

Claims

1-20. -20. (canceled)

21. Brake control circuit, wherein the brake control circuit comprises a first switch that controls the electricity supply of the winding of the brake, which switch is switched in a controlled manner with short pulses by the control of the electricity supply of the winding of the brake, and thus the braking function is controlled.

22. Brake control circuit according to claim 21, wherein after the electricity supply of the winding of the brake has been disconnected, the energy stored in the winding is discharged into the intermediate circuit of the brake control circuit via the release branch.

23. Brake control circuit according to claim 21, wherein when the voltage of the intermediate circuit exceeds a set limit value, energy is discharged into the attenuation circuit fitted in parallel with the winding of the brake.

24. Brake control circuit according to claim 21, wherein a capacitor is connected between the rails that transfer output current and return current to the intermediate circuit of the brake control circuit.

25. Brake control circuit according to claim 21, wherein the current of the brake is adjusted towards the set reference for brake current by switching the first controllable switch with short pulses.

26. Brake control circuit according to claim 21, wherein a first controllable switch, which is switched with short pulses, is fitted in series with a winding of the brake;

a second controllable switch, which when controlling the brake is kept continuously closed at the same time as the first controllable switch is switched with short pulses, is further fitted in series with the winding of the brake; and

the electricity supply from the intermediate circuit to the winding of the brake is arranged to be disconnected by opening the second controllable switch.

27. Brake control circuit according to claim 21, wherein the first and second switch are arranged to be controlled on the basis of the status data of the safety circuit of the elevator.

28. Brake control circuit according to claim 21, wherein when detecting a line-to-earth short-circuit of the brake only the first switch is closed, and the line-to-earth short-circuit is in this case determined on the basis of the current flowing through the first switch.

29. Elevator system, which comprises a movement control system, which adjusts the movement of the elevator car according to the set movement reference, and

wherein the elevator system comprises a brake control circuit according to claim 21, for controlling the brake of the elevator.

30. Elevator system according to claim 29, wherein the elevator system comprises a safety circuit;

and

in connection with an emergency stop the safety circuit of the elevator inspects the operating condition of the movement control system.

31. Elevator system according to claim 30, wherein when an operational nonconformance of the movement control system is detected, the safety circuit disconnects the electricity supply to the winding of the brake by opening the first and the second controllable switch.

32. Elevator system according to claim 30, wherein when the movement control system is detected to be in working order, the safety circuit permits electricity supply to the winding of the brake with the control of the first and the second controllable switch;

and

the movement control system regulates in this case by means of the brake control circuit the movement of the elevator car during an emergency stop by adjusting the current of the winding of the brake and thus the braking force of the brake of the elevator so that the movement of the elevator car approaches the reference set for the movement.

33. Elevator system according to claim 29, wherein the motor control unit of the elevator comprises a non-volatile memory, in which the parameters of the brake are stored, at least one of which parameters is the reference for the current of the winding of the brake and also the limit value for the voltage of the winding of the brake that corresponds to this;

and

the parameters are transferred from the motor control unit to the brake control circuit via the communications channel made between them.

34. Elevator system according to claim 29, wherein the voltage of the winding of the brake is limited to the limit value for the voltage of the winding of the brake at any given time with the control of the first controllable switch.

35. Elevator system according to claim 29, wherein the elevator system comprises at least two brakes of the elevator, both of which brake a moving part of the same elevator machine.

36. Elevator system according to claim 35, wherein the electricity supply to the winding of the first brake is controlled with the first controllable switch;

a third controllable switch, which is fitted in series with the winding of the second brake, is fitted to the brake control circuit; and

the electricity supply to the winding of the second brake is controlled by switching the third controllable switch with short pulses.

37. Elevator system according to claim 35, wherein a fourth controllable switch is fitted to the brake control circuit;

the electricity supply from the intermediate circuit to the winding of the first brake is arranged to be disconnected by opening a second controllable switch; and

the electricity supply from the intermediate circuit to the winding of the second brake is arranged to be disconnected by opening a fourth controllable switch.

38. Elevator system according to claim 35, wherein the brake control circuit is arranged to close in connection with an emergency stop at first only a first brake;

and

the brake control circuit is arranged to close also a second brake, if the movement of the elevator car determined by the movement control system during an emergency stop decelerates by less than the minimum deceleration during an emergency stop according to the reference set for movement.

39. Method for controlling the brake of the elevator, comprising the steps of:

fitting a movement control system into the elevator;

adjusting the movement of the elevator car according to a set movement reference;

fitting a brake control circuit according to claim 21 into the elevator system; and

controlling the brake of the elevator with the brake control circuit.

40. Method according to claim 39, wherein

the operating condition of the movement control system is determined in connection with an emergency stop, and when it is detected that the movement control system is in working order,

the movement of the elevator car during an emergency stop is regulated with the movement control system by means of the brake control circuit by adjusting the current of the winding of the brake and thus the braking force of the brake of the elevator so that the movement of the elevator car approaches the reference set for the movement.