Elevator Lifting Platform Safety Rope Arresting Mechanism

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Solution Overview

Problem

The existing elevator systems in construction phases face challenges in safely raising the lifting platform without guide rails, leading to a risk of accidents and equipment damage due to the inability to use safety brakes for fall protection.

Innovation Solution

A rope safety device with a safety rope and rope stop device is installed between the lifting platform and a rope pulley support, allowing the safety rope to be arranged outside the free space above the center of gravity, preventing further lowering after exceeding a predetermined speed, and ensuring the lifting platform maintains a horizontal position during braking.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Length of moving object

If the lifting platform is raised without guide rails in the uppermost section of the elevator shaft, then the lifting platform can be positioned to raise the machine platform to higher levels, but the risk of the lifting platform falling increases due to the inability to use safety brakes

Engineering Contradiction:
Improvelifting height of machine platformVSAvoidfall protection of lifting platform
Core Design Contradiction:
Length of moving objectVSReliability

Solution Approach 1:

A safety rope is introduced as an intermediary fall protection device between the lifting platform and the shaft structure. The safety rope runs through guide eyes in the shaft and is connected to the lifting platform, providing passive fall protection without requiring active braking systems or guide rails in the uppermost section.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The safety rope system is pre-installed and positioned in advance before the lifting platform is raised to higher levels. The rope is tensioned and ready to immediately arrest any fall, providing beforehand protection against the identified hazard of falling in the guide rail-free zone.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

2Reliability

If a safety rope is installed for fall protection of the lifting platform, then the risk of falling is reduced, but the safety rope may interfere with crane operations if not properly positioned

Engineering Contradiction:
Improvefall protection of lifting platformVSAvoidcrane operation
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The safety rope system is positioned in specific locations (through guide eyes in the shaft, away from the centerline) to provide fall protection while leaving the central operating space clear for crane movements. Different sections of the shaft have the safety rope routed through locally optimized paths that avoid interference with lifting operations.

Inventive Principle:
Principle #3Local quality

3Device complexity

If the lifting platform is equipped with passive fall protection through a safety rope, then the complexity of active braking systems is reduced, but the system requires careful positioning and tensioning of the rope

Engineering Contradiction:
Improvefall protection systemVSAvoidinstallation of safety rope
Core Design Contradiction:
Device complexityVSEase of manufacture

Solution Approach 1:

The fall protection system is segmented into discrete components: fixed guide eyes in the shaft, a continuous safety rope, and connection points on the lifting platform. This segmentation allows for modular installation where each component can be independently positioned and adjusted, simplifying the overall installation process despite the need for precise positioning.

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

This solution effectively minimizes the risk of the lifting platform falling and reduces the risk of accidents for assembly personnel by ensuring the lifting platform remains stable and secure, even in areas without guide rails, while allowing for unhindered crane operation.

Implementation Method 1

a rope stop device attached to the lifting platform, by means of which the last load-bearing rope section can be blocked and thus a further descent of the lifting platform can be prevented after the speed of the last load-bearing rope section has exceeded a predetermined limit relative to the rope stop device

Methodology Applied
Scientific EffectSpeed detection:

Implementation Method 2

a rope arrester comprising a safety rope arranged between the lifting platform and a rope pulley support fixed above the lifting platform in the elevator shaft according to the principle of a pulley block with at least two load-bearing rope sections

Methodology Applied
Scientific EffectMechanical advantage: Mechanical Advantage

Data Source

PatentEP4172096B1Method for installing an elevator installation and elevator installation
Publication Date: 2024.10.02 INVENTIO AG
  • EP4172096B1 patent drawingFigure 1
  • EP4172096B1 patent drawingFigure 2
  • EP4172096B1 patent drawingFigure 3

AI summary

The invention relates to a method for building a lift system (1) in a building which is currently being built, in which method a usable lifting height of the lift system is adapted to an increasing height of the building, and in which method - in the lift shaft (2), a liftable and temporarily lockable machine platform (10) is installed, on which a lift-driving machine (11) having a traction drive (12) is located, - a lift car (3) and a counterweight (4) are suspended from the machine platform (10) via suspension means (15), so that the lift car (3) and the counterweight (4) can be moved upwards and downwards along guide rails in the lift shaft (2) by means of the traction drive (12) via the suspension means (15), - above the machine platform (10), a lifting platform (17) is installed which is liftable and temporarily lockable in the lift shaft (2) and by means of which the machine platform (10) is lifted with the lift car (3) or the counterweight (4) when the usable lifting height of the lift car is intended to be adapted to a current height of the lift shaft (2), and wherein - prior to lifting the machine platform (10), the lifting platform (17) is lifted to a higher level by means of a building crane (40) or another lifting device (35), and wherein the lifting platform (17) is equipped with a cable catch device (25.1) which comprises a safety cable (31), at least two load-bearing cable sections of which are arranged, according to the Bowden cable principle, between the lifting platform (17) and a cable pulley support (26) fixed above the lifting platform in the lift shaft (2), wherein a first load-bearing cable section of the safety cable (31) is fixed to the lifting platform (17) or is fixed in a stationary manner above the lifting platform, and a last load-bearing cable section is guided through a cable stop apparatus (30) which is fastened to the lifting platform (17) and by means of which the last load-bearing cable section is blocked and further lowering of the lifting platform (17) is thereby prevented after the speed of the last load-bearing cable section has exceeded a specified limit in relation to the cable stop apparatus (30).