Elevator Apron Device with Rotating Protective Element
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing apron devices for elevators with limited pit depth are inadequate in preventing falls into the elevator shaft, especially during uncontrolled movements or when gaps form between the elevator car and the landing.
Innovation Solution
The apron device comprises a first and second protective element, both vertically oriented and made of rigid material, which move upward when the first protective element contacts the pit or obstacle. The second protective element transitions from a vertical to a transverse position, allowing for automatic adjustment and enhanced protection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the apron device uses a fixed structure, then it is simple in construction, but it cannot adapt to gaps formed during elevator movement and fails to provide adequate protection
Solution Approach 1:
The apron device employs movable protective elements that can dynamically adjust their position. The first protective element moves vertically along guide rails, and the second protective element rotates about a horizontal axis, allowing the structure to adapt to gaps formed during elevator car movement while maintaining safety protection functionality
Solution Approach 2:
The apron device is divided into multiple independent protective elements (first protective element and second protective element) that can move and adjust independently. This segmentation allows each element to respond to specific movement conditions and provides comprehensive protection against various failure modes
2Reliability
If the apron device extends a long skirt below the elevator car, then it provides better protection against falls, but it requires greater pit depth which is not available in limited depth installations
Solution Approach 1:
The apron device uses movable protective elements that can extend and retract based on the elevator car's position. The first protective element moves vertically to maintain protection during downward movement, while the second protective element rotates to provide additional coverage, enabling effective fall protection without requiring excessive pit depth
Solution Approach 2:
The second protective element introduces a rotational degree of freedom about a horizontal axis, allowing it to move from a vertical position to a horizontal position. This dimensional change enables the apron device to provide extended protection coverage without increasing the vertical pit depth requirement
3Strength
If the protective elements are made of rigid material, then they provide sufficient bending stiffness and safety, but they cannot flex to accommodate movement and contact with obstacles
Solution Approach 1:
The rigid protective elements are designed to move as rigid bodies along predetermined paths. The first protective element translates vertically along guide rails, and the second protective element rotates about a horizontal axis. This dynamic movement of rigid elements allows them to maintain bending stiffness for safety while adapting to the elevator car's movement and obstacle contact conditions
Data Source
AI summary
An apron device, an elevator car and method of protecting falling into an elevator shaft. The apron device comprises a first protective element and a second protective element which are both located under a door sill of an elevator car. The elements form together a bending stiff sleeve structure which can move in relation to the elevator car. The first protective element can lift the second protective element being closer to the elevator car. When the second protective element is lifted, its upper part moves in transversal direction towards a space below a bottom of the elevator car. The first protective element is moved only in vertical direction.