Elevator Slide Door Obstruction Detection via Reflected Light
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional door safety apparatuses are prone to malfunctions due to adhering rubbish and dust blocking light from light-emitting photoelectric tubes, which affects the detection of obstructions.
Innovation Solution
A sliding door apparatus with a light emitter positioned on either the upper or lower portion of a doorway illuminating a surface on a facing lower frame, and a light receiver on the same doorway to detect obstructions by reflecting light, reducing the likelihood of debris accumulation and ensuring stable obstruction detection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If light-receiving photoelectric tubes are disposed so as to face upward inside the opening portion on the doorsill, then obstruction detection function is provided, but opaque rubbish and dust easily adhere onto the transparent cover and block the light, increasing the likelihood of malfunction
Solution Approach 1:
The patent inverts the conventional upward-facing light receiver configuration by positioning the light receiver to face downward or horizontally, receiving reflected light from the illuminated surface. This inversion prevents dust and rubbish from adhering to the light receiver, thereby maintaining reliable obstruction detection without the malfunction issues caused by contaminated transparent covers.
Solution Approach 2:
The patent introduces an illuminated surface (the surface of the lower frame) as an intermediary element. The light emitter illuminates this surface, and the light receiver receives the reflected light from it. This intermediary surface acts as a mediator that prevents direct exposure of the light receiver to dust and rubbish while still enabling effective obstruction detection through reflected light.
2Object-affected harmful factors
If light emitter and light receiver are positioned to illuminate and receive reflected light from the framed surface, then dust adhesion is reduced, but detection precision for small obstructions must be maintained
Solution Approach 1:
The patent applies local quality by positioning the light emitter and light receiver at specific locations on the doorway frame (upper or lower portions) and directing the light to a specific illuminated surface. This localized configuration optimizes both the reduction of dust adhesion and the maintenance of detection precision for small obstructions by carefully controlling the light path and reception geometry.
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 configuration minimizes the occurrence of malfunctions caused by debris and allows for stable detection of obstructions, even small or slender objects, by positioning the light emitter and receiver to avoid dust accumulation and enabling precise detection across a wider range.
Implementation Method 1
a light emitter that is disposed on a first portion of either an upper portion or a lower portion of the first doorway, and that illuminates an illuminated surface that is a surface of the second lower frame that faces the first lower frame; a light receiver that is disposed on a second portion of the upper portion or the lower portion of the first doorway, and that receives light that is emitted from the light emitter and reflected by the illuminated surface
Data Source
Figure 1
Figure 2
Figure 3
AI summary
In a sliding door apparatus, a first lower frame is disposed on a lower portion of a first doorway, and a second lower frame is disposed on a lower portion of a second doorway. A light emitter that illuminates an illuminated surface that is a surface of the second lower frame that faces the first lower frame is disposed on a first portion of either an upper portion or a lower portion of the first doorway. A light receiver that receives light that is emitted from the light emitter and reflected by the illuminated surface is disposed on a second portion of the upper portion or the lower portion of the first doorway. A determination controlling portion determines presence or absence of an obstruction by detecting whether or not the light that is emitted from the light emitter and reflected by the illuminated surface is received by the light receiver.