Hoistway Liner Bumpers for Elevator Roping Sway Mitigation

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Solution Overview

Problem

Ultra-high rise buildings face challenges with static deflection and sway conditions that can cause undesired movement of elevator roping assemblies, leading to potential damage or interference with normal elevator operation, as existing sway mitigation devices may not effectively address these issues, especially when they need to move into the pathway of the elevator car or are unable to counteract building drift.

Innovation Solution

The implementation of a hoistway liner assembly with strategically placed bumpers, comprising rollers made of compressible materials like rubber or polyurethane, which create a protected area around the load-bearing assembly, preventing contact with the interior hoistway walls by spanning across multiple walls and allowing the elevator car to move freely while absorbing impacts, and are positioned to remain effective during static building drift and temporary sway conditions without requiring movement into the elevator car's pathway.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If sway mitigation devices are moved into the pathway of the elevator car to counteract building drift, then protection against static deflection is improved, but interference with normal elevator operation occurs

Engineering Contradiction:
Improveprotection against static deflectionVSAvoidnormal elevator operation
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The sway mitigation device is designed to be movable between a retracted position (normal operation) and an extended position (protection mode). The device can dynamically adjust its position based on building sway conditions, allowing it to provide protection when needed while avoiding interference with normal elevator car movement

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The sway mitigation device is positioned in advance within the hoistway at locations where it can effectively counteract building drift. The device is pre-configured to extend into the pathway only when sway conditions occur, rather than occupying the pathway continuously, thus preventing interference with normal operation while maintaining readiness to protect against static deflection

Inventive Principle:
Principle #10Preliminary action

2Ease of operation

If sway mitigation devices are retracted out of the pathway to avoid interference, then normal elevator operation is maintained, but protection during sway conditions is reduced

Engineering Contradiction:
Improvenormal elevator operationVSAvoidprotection during sway conditions
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The device transitions from a static configuration to a dynamic one, capable of extending from a retracted state (during normal operation) to an active state (during sway conditions). This dynamic capability allows the system to maintain both ease of operation and reliability by adapting to different operational conditions

Inventive Principle:
Principle #15Dynamics

3Reliability

If car followers are added to limit compensation rope motions, then roping sway is reduced, but weight of the machine and ropes increases

Engineering Contradiction:
Improveroping sway reductionVSAvoidweight of machine and ropes
Core Design Contradiction:
ReliabilityVSWeight of moving object

Solution Approach 1:

Instead of adding weight to the moving components (car followers attached to the elevator car), the sway mitigation function is extracted and placed as separate, stationary devices mounted on the hoistway structure. This eliminates the need to increase the weight of the machine and ropes while still achieving roping sway reduction through the stationary bumpers that guide and stabilize the ropes

Inventive Principle:
Principle #2Taking out (Extraction)

4Reliability

If multiple sway mitigation devices are installed to address building drift, then protection coverage is improved, but device complexity increases

Engineering Contradiction:
Improveprotection coverageVSAvoidnumber of sway mitigation devices
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The hoistway is divided into multiple zones, each equipped with its own sway mitigation device. This segmentation allows each device to independently protect a specific section, providing comprehensive coverage throughout the hoistway while keeping each individual device simple and manageable

Inventive Principle:
Principle #1Segmentation

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The hoistway liner assembly effectively prevents contact between the load-bearing assembly and the hoistway interior, ensuring continuous protection and safe operation during static building drift and sway conditions, without the need for actuating mechanisms, thus maintaining elevator system integrity and functionality.

Implementation Method 1

the rollers comprise a compressible material that absorbs at least some of an impact associated with contact between the load bearing assembly and a contacted one of the rollers

Methodology Applied
Scientific EffectCompression: Compression

Data Source

PatentEP3398897B1Elevator system including a protective hoistway liner assembly
Publication Date: 2022.01.12 OTIS ELEVATOR CO
  • EP3398897B1 patent drawingFigure 1
  • EP3398897B1 patent drawingFigure 2~4
  • EP3398897B1 patent drawingFigure 5~6

AI summary

An illustrative example elevator system (20) includes a hoistway (26) that establishes a vertical pathway. The hoistway (26) has an interior border established by a plurality of stationary boundaries that each have a height aligned with a vertical length of the hoistway. Each of the stationary boundaries has a width generally perpendicular to the height. An elevator car (22) is within the hoistway (26). At least one vertically extending load bearing assembly (28) includes a plurality of elongated load bearing members extending along a vertical path and facilitating movement or support of the elevator car (22). At least one hoistway liner assembly (50) is situated in the hoistway (26). The hoistway liner assembly (50) includes a plurality of bumpers (52) that each have an axis that is generally perpendicular to the vertical length of the hoistway (26). The axes of at least two of the bumpers (52) are non-parallel. The bumpers (52) collectively establish a protected area sufficient for preventing contact between the load bearing assembly (28) and the interior border of the hoistway (26) if there is lateral movement of any of the load bearing members relative to the vertical path in at least two generally perpendicular directions.