Underslung Elevator Car Sheave Nesting and Vibration Isolation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional underslung elevator car designs face challenges in maintaining compactness and achieving vibration isolation when integrating the cabin and frame structure, leading to potential increases in size and pit depth requirements.

Innovation Solution

An integrated elevator car structure with a sheave assembly supported beneath the floor, utilizing subframe beams and isolation members to nest the sheaves within the platform thickness, isolating vibrations and maintaining compactness without increasing the overall size.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If an integrated elevator car frame and cabin structure is used, then manufacturing complexity is reduced, but vibration isolation becomes difficult to achieve

Engineering Contradiction:

Improvemanufacturing complexityVSAvoidvibration isolation

Core Design Contradiction:

Device complexityVSObject-affected harmful factors

Solution Approach 1:

The integrated elevator car structure is segmented into distinct functional zones: the cabin area, the sheave assembly area, and vibration isolation elements positioned between them. This segmentation allows the cabin to be isolated from sheave vibrations while maintaining the integrated structure's manufacturing advantages.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Vibration isolating elements are introduced as intermediary components between the integrated frame-cabin structure and the sheave assembly. These intermediaries absorb and isolate vibrations, preventing them from transmitting to the cabin while allowing the integrated structure to maintain its structural unity.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Volume of moving object

If an underslung arrangement with sheaves beneath the elevator car is used, then space utilization is improved, but pit depth requirements increase

Engineering Contradiction:

Improvespace utilizationVSAvoidpit depth

Core Design Contradiction:

Volume of moving objectVSLength of stationary object

Solution Approach 1:

The sheave assembly is nested within the platform thickness of the elevator car, positioning the sheaves and subframe beams above the lowermost surface on the support beam. This nesting approach utilizes the vertical space within the existing platform depth, avoiding the need to increase pit depth while maintaining the underslung configuration's space utilization benefits.

Inventive Principle:

Principle #7Nested doll (Nesting)

3Volume of moving object

If the sheave assembly is positioned beneath the floor surface, then compactness is maintained, but vibration transmission to the cabin increases

Engineering Contradiction:

ImprovecompactnessVSAvoidvibration transmission

Core Design Contradiction:

Volume of moving objectVSObject-affected harmful factors

Solution Approach 1:

Vibration isolating elements serve as intermediaries positioned between the sheave assembly and the elevator car structure. These elements selectively transmit or block vibrations, allowing the sheave assembly to remain in its compact position beneath the floor surface while preventing excessive vibration transmission to the cabin.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The vibration isolating elements change the dynamic parameters of the system by providing flexibility and damping characteristics. This modifies the vibration transmission path, reducing the propagation of high-frequency sheave vibrations to the cabin while maintaining the structural integrity of the compact design.

Inventive Principle:

Principle #35Parameter changes

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 solution effectively isolates vibrations, reduces noise, and maintains space savings by allowing the sheave assembly to fit within the existing platform thickness, preventing vibration and noise transfer to the cabin while supporting the underslung configuration without enlarging the elevator car or pit depth.

Implementation Method 1

A plurality of isolation members are between the sheave assembly and the elevator car for isolating an interior of the cabin from vibrations associated with movement of the sheaves

Methodology Applied

Scientific EffectVibration isolation: Damping

Data Source

PatentUS10532910B2Underslung elevator car configuration

Publication Date: 2020.01.14 OTIS ELEVATOR CO

AI summary

An exemplary elevator system includes an elevator car having an integrated cabin and car frame structure including a platform thickness between a floor surface in the cabin and a lowermost surface on a support beam used for supporting the car beneath the floor surface. A sheave assembly is supported beneath the floor surface. The sheave assembly includes a plurality of sheaves and a plurality of subframe beams. The sheaves and subframe beams fit within the platform thickness such that the subframe beams and the sheaves are no lower than the lowermost surface on the support beam. A plurality of isolation members are between the sheave assembly and the elevator car for isolating an interior of the cabin from vibrations associated with movement of the sheaves.