Vibration damping device and elevator apparatus

A vibration damping device for reducing vibration of a long structure, comprising:

• a displacement amplifier arranged along a given position in a longitudinal direction of the structure, the displacement amplifier being configured to amplify a displacement of the structure;
• and
• a limiting member that controls displacement amplification performed by the displacement amplifier such that the displacement of the structure amplified by the displacement amplifier does not become greater than a first displacement, the first displacement being the displacement of the structure by which the structure is not allowed to return to an equilibrium position of the vibration, wherein
• when the structure is an elevator rope,
• the displacement amplifier is arranged along a given position in a longitudinal direction of the elevator rope, and amplifies a displacement of the elevator rope,
• the limiting member 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 the first displacement,
• the elevator rope includes a plurality of main ropes that are connected to a car and a counterweight of an elevator and are wound on a sheave, and
• the vibration damping device includes a restraining member that maintains a constant distance between each of the plurality of main ropes in a horizontal direction.

A vibration damping device for reducing vibration of a long structure, comprising:

• a displacement amplifier arranged along a given position in a longitudinal direction of the structure, the displacement amplifier being configured to amplify a displacement of the structure;
• and
• a limiting member that controls displacement amplification performed by the displacement amplifier such that the displacement of the structure amplified by the displacement amplifier does not become greater than a first displacement, the first displacement being the displacement of the structure by which the structure is not allowed to return to an equilibrium position of the vibration, wherein
• when the structure is an elevator rope,
• the displacement amplifier is arranged along a given position in a longitudinal direction of the elevator rope, and amplifies a displacement of the elevator rope,
• the limiting member 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 the first displacement, and
• one of the limiting member and the displacement amplifier includes a roller adapted to contact the elevator rope.

A vibration damping device for reducing vibration of a long structure, comprising:

• a displacement amplifier arranged along a given position in a longitudinal direction of the structure, the displacement amplifier being configured to amplify a displacement of the structure;
• a limiting member that includes a mechanical structure to limit a movement and thereby control displacement amplification performed by the displacement amplifier such that the displacement of the structure amplified by the displacement amplifier does not become greater than a first displacement, the first displacement being the displacement of the structure by which the structure is not allowed to return to an equilibrium position of the vibration;
• and
• a coupling portion that is coupled to the long structure to transmit a force from the displacement amplifier to the long structure, wherein
• the mechanical structure of the limiting member is arranged between the displacement amplifier and the long structure.

A vibration damping device for reducing vibration of a long structure, comprising:

• a displacement amplifier arranged along a given position in a longitudinal direction of the structure, the displacement amplifier being configured to amplify a displacement of the structure;
• and
• a limiting member that includes a mechanical structure to limit a movement and thereby control displacement amplification performed by the displacement amplifier such that the displacement of the structure amplified by the displacement amplifier does not become greater than a first displacement, the first displacement being the displacement of the structure by which the structure is not allowed to return to an equilibrium position of the vibration, wherein
• when the long structure is an elevator rope,
• the displacement amplifier is arranged along a given position in a longitudinal direction of the elevator rope, and amplifies a displacement of the elevator rope,
• the limiting member 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 the first displacement,
• the displacement amplifier includes an unstable link mechanism that generates a negative stiffness force utilizing a displacement of one or more links, and
• the limiting member controls the displacement of at least one of the one or more links.