Vibration damping system and elevator apparatus

Patent metadata

Field	Value
Publication number	US-12049385-B2
Application number	US-201817051799-A
Country	US
Kind code	B2
Filing date	Dec 3, 2018
Priority date	May 15, 2018
Publication date	Jul 30, 2024
Grant date	Jul 30, 2024

Abstract

An object of the invention is to provide a vibration damping system that can avoid the occurrence of resonance of an elevator rope regardless of the vibration frequency of a vibration source. A vibration damping system (200) includes a displacement amplifier (7), a calculation unit (66), and a displacement amplification control unit (67). The displacement amplifier (7) is arranged along a given position in the longitudinal direction of the elevator rope. The displacement amplifier (7) amplifies a displacement due to vibration of the elevator rope based on a variable amplification factor. The calculation unit (66) calculates the natural frequency of the elevator rope. The displacement amplification control unit (67) controls the displacement amplification of the displacement amplifier (7) based on the natural frequency calculated by the calculation unit (66) and a preset vibration frequency.

First claim

The invention claimed is:

1. A vibration damping system comprising:
a displacement amplifier arranged along a given position in a longitudinal direction of an elevator rope, the displacement amplifier being configured to amplify a displacement due to vibration of the elevator rope when the displacement amplifier is in a first state, and not amplify the displacement due to vibration of the elevator rope when the displacement amplifier is in a second state; and
processing circuitry
to calculate a natural frequency of the elevator rope; and
to switch a state of the displacement amplifier based on the natural frequency calculated and a preset vibration frequency.

2. The vibration damping system according to claim 1 , wherein the displacement amplifier includes at least one electromagnet arranged facing the elevator rope, the electromagnet being configured to be excited and generate a magnetic field when the displacement amplifier is in the first state.

3. The vibration damping system according to claim 1 , wherein the displacement amplifier includes a pair of electromagnets each arranged facing the elevator rope, each of the pair of electromagnets being configured to be excited and generate a magnetic field when the displacement amplifier is in the first state.

4. The vibration damping system according to claim 1 , wherein the displacement amplifier includes
a displacement measurement instrument that measures the displacement of the elevator rope, and
at least one actuator that, when the displacement amplifier is in the first state, contacts the elevator rope from both sides in a displacement direction of the elevator rope, and applies a force to the elevator rope in a direction in which the displacement of the elevator rope measured by the displacement measurement instrument is amplified.

5. The vibration damping system according to claim 1 , wherein the displacement amplifier includes
a displacement measurement instrument that measures the displacement of the elevator rope, and
a pair of actuators that, when the displacement amplifier is in the first state, contact the elevator rope from both sides in a displacement direction of the elevator rope, and apply a force to the elevator rope in a direction in which the displacement of the elevator rope measured by the displacement measurement instrument is amplified.

6. The vibration damping system according to claim 1 ,
wherein:
the processing circuitry calculates as a second natural frequency the natural frequency of the elevator rope when the displacement amplifier is in the second state, and
the processing circuitry switches the state of the displacement amplifier to the first state when the second natural frequency is included in a limited range that includes the vibration frequency.

7. The vibration damping system according to claim 1 ,
wherein:
the processing circuitry calculates as a first natural frequency the natural frequency of the elevator rope when the displacement amplifier is in the first state, and calculates as a second natural frequency the natural frequency of the elevator rope when the displacement amplifier is in the second state, and
the processing circuitry switches the state of the displacement amplifier to the first state when a difference between the first natural frequency and the vibration frequency is greater than a difference between the second natural frequency and the vibration frequency, and switches the state of the displacement amplifier to the second state when the difference between the first natural frequency and the vibration frequency is smaller than the difference between the second natural frequency and the vibration frequency.

8. The vibration damping system according to claim 1 , wherein when the elevator rope is a main rope for moving a car of an elevator,
the displacement amplifier amplifies a displacement due to vibration of the main rope when the displacement amplifier is in the first state, and does not amplify the displacement due to vibration of the main rope when the displacement amplifier is in the second state, and
the processing circuitry calculates the natural frequency of the main rope.

9. The vibration damping system according to claim 8 , wherein the processing circuitry switches the state of the displacement amplifier based on a moving direction of the car.

10. The vibration damping system according to claim 1 , further comprising a limiting member that controls displacement amplification performed by the displacement amplifier such that the displacement of the elevator rope amplified by the displacement amplifier does not become greater than a first displacement, the first displacement being the displacement of the elevator rope by which the elevator rope is not allowed to return to an equilibrium position of the vibration.

11. An elevator apparatus comprising the vibration damping system according to claim 1 .

12. A vibration damping system comprising:
a displacement amplifier arranged along a given position in a longitudinal direction of an elevator rope, the displacement amplifier being configured to amplify a displacement due to vibration of the elevator rope when the displacement amplifier is in a first state, and not amplify the displacement due to vibration of the elevator rope when the displacement amplifier is in a second state; and
processing circuitry
to calculate a natural frequency of the elevator rope; and
to switch a state of the displacement amplifier based on the natural frequency calculated and a preset vibration frequency,
wherein:
the processing circuitry calculates as a first natural frequency the natural frequency of the elevator rope when the displacement amplifier is in the first state, and
the processing circuitry switches the state of the displacement amplifier to the second state when the first natural frequency is included in a limited range that includes the preset vibration frequency.

13. The vibration damping system according to claim 12 , wherein the processing circuitry switches the state of the displacement amplifier based on the limited range that has been determined based on a response magnification factor.

14. A vibration damping system comprising:
a displacement amplifier arranged along a given position in a longitudinal direction of an elevator rope, the displacement amplifier being configured to amplify the displacement due to vibration of the elevator rope based on a variable amplification factor; and
processing circuitry
to calculate a natural frequency of the elevator rope; and
to change the amplification factor of the displacement amplifier based on the natural frequency calculated and a preset vibration frequency.

15. The vibration damping system according to claim 14 , wherein the displacement amplifier includes a pair of electromagnets each arranged facing the elevator rope, each of the pair of electromagnets being configured to be excited with a current value corresponding to the amplification factor and generate a magnetic field.

16. The vibration damping system according to claim 14 , wherein the displacement amplifier includes
a pair of magnet units each arranged facing the elevator rope, and
a pair of actuators each configured to move each of the pair of magnet units to a position corresponding to the amplification factor, thereby changing a distance between each of the pair of magnet units and the elevator rope.

17. The vibration damping system according to claim 14 , wherein the displacement amplifier includes
a displacement measurement instrument that measures the displacement of the

Assignees

• Mitsubishi Electric Corp

Inventors

• Saito Eiichi
• Hirai Takahide
• Watanabe Seiji
• Nakazawa Daisuke
• Fukui Daiki
• Asamura Tomohiro
• Chikada Yusuke

Classifications

• F16F15/035 Primary

  by use of eddy or induced-current damping (dynamo-electric brakes of the eddy-current type H02K49/04) · CPC title

• F16F2230/0029

  Location, co-location · CPC title

• F16F15/022

  using dampers and springs in combination · CPC title

• B66B7/1215

  specially adapted for ropes or cables · CPC title

• B66B7/10

  for equalising rope or cable tension · CPC title