Elevator Toe Guard Assembly with Telescopic Folding Panels

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional toe guards in elevator systems do not allow for sufficient clearance when the elevator car needs to descend low, especially in systems without or with reduced pit sizes, limiting the car's ability to reach necessary landing positions without bumping into the hoistway.

Innovation Solution

A moveable toe guard assembly with a first panel and a second panel that slides and telescopes, allowing the second panel to retract and the first panel to pivot, reducing the overall height as the elevator descends, and incorporating a folding mechanism to further minimize clearance when necessary.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Length of moving object

If a conventional rigid toe guard is used, then the toe guard provides stable protection, but it requires significant clearance beneath the elevator car, preventing the car from descending low enough in reduced-pit or pitless systems

Engineering Contradiction:
Improveclearance beneath elevator carVSAvoidprotection function of toe guard
Core Design Contradiction:
Length of moving objectVSReliability

Solution Approach 1:

The toe guard assembly transitions from a static rigid structure to a dynamic multi-position structure. The panels can pivot between extended (vertical) and retracted (horizontal/near-horizontal) positions, allowing the clearance beneath the car to change from approximately one meter to a minimal amount, enabling operation in reduced-pit and pitless systems while maintaining protection when needed

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The toe guard is divided into multiple panels (first panel, second panel, third panel) that can move independently or collectively. This segmentation allows different portions of the toe guard to be in different positions simultaneously, providing flexibility in maintaining protection while reducing overall clearance requirements

Inventive Principle:
Principle #1Segmentation

2Reliability

If the toe guard is extended vertically downward, then maximum protection is provided, but the elevator car cannot descend to necessary landing positions in systems without pits

Engineering Contradiction:
Improveprotection function of toe guardVSAvoiddistance from car bottom to hoistway surface
Core Design Contradiction:
ReliabilityVSLength of moving object

Solution Approach 1:

The toe guard assembly is designed with movable panels that can change orientation from vertical (extended) to horizontal (retracted). This dynamic reconfiguration allows the car to descend to the hoistway surface in pitless systems while the toe guard can be positioned horizontally to avoid interference, or vertically when protection is needed

Inventive Principle:
Principle #15Dynamics

3Length of moving object

If a moveable toe guard with multiple panels is used, then clearance is reduced allowing lower descent, but the device complexity increases

Engineering Contradiction:
Improveclearance beneath elevator carVSAvoidstructure of toe guard assembly
Core Design Contradiction:
Length of moving objectVSDevice complexity

Solution Approach 1:

The toe guard is segmented into multiple panels connected by folding mechanisms, allowing independent movement of each panel. This segmentation enables the complex reconfiguration capability while distributing the mechanical complexity across multiple simpler, modular components rather than one complex mechanism

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The second panel is telescopically received within the first panel, and the third panel is telescopically received within the second panel. This nested arrangement allows multiple panels to occupy overlapping spaces when retracted, minimizing the overall footprint and complexity of the retraction mechanism while maximizing the clearance reduction capability

Inventive Principle:
Principle #7Nested doll (Nesting)

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

Enables the elevator car to descend closer to the surface by adjusting the toe guard's height, accommodating various pit depths and eliminating the need for a pit, ensuring safe and efficient operation.

Implementation Method 1

a folding mechanism connected to the first panel and configured to transform mechanical energy to move the first panel from the extended position toward the retracted position

Methodology Applied
Scientific EffectMechanical Advantage: Mechanical Advantage

Data Source

PatentEP2688826B1Toe guard assembly for an elevator system
Publication Date: 2022.06.15 OTIS ELEVATOR CO
  • EP2688826B1 patent drawingFigure 1
  • EP2688826B1 patent drawingFigure 2~3
  • EP2688826B1 patent drawingFigure 4~6

AI summary

An exemplary elevator toe guard assembly includes a first panel. A second panel is slidable relative to the first panel in a first direction between an extended position and a retracted position. The first panel moves in a second, different direction from an extended position toward a folded position responsive to the second panel moving toward the retracted position.