Elevator Ventilation System CO2 Sensor Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Elevator cars without mechanical ventilation systems face significant CO2 buildup when occupants are trapped due to lack of air exchange, especially during power failures, as natural ventilation is insufficient when stationary, posing a risk to occupant safety.

Innovation Solution

A mechanical ventilation system comprising a fan, CO2 sensor, evaluation unit, and control unit that activates only when the elevator car is stationary and CO2 levels exceed a specified value or change rapidly, ensuring air exchange between the car and its surroundings.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If a mechanical ventilation system is installed in the elevator car, then CO2 buildup is reduced and air quality is maintained, but device complexity increases

Engineering Contradiction:
ImproveCO2 buildupVSAvoidventilation system complexity
Core Design Contradiction:
Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The ventilation system is segmented into distinct functional components: a fan unit for air movement, a CO2 sensor for detection, an evaluation unit for decision-making, and a control unit for operation. This segmentation allows each component to perform its specific function efficiently while keeping the overall system manageable and not overly complex.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system employs automatic detection and control mechanisms where the CO2 sensor continuously monitors air quality, the evaluation unit automatically determines when ventilation is needed based on CO2 levels and elevator motion status, and the control unit autonomously activates the fan without requiring manual intervention. This self-service capability reduces operational complexity while maintaining effective CO2 control.

Inventive Principle:
Principle #25Self-service

2Object-affected harmful factors

If the ventilation system operates continuously, then air quality is maintained, but energy consumption increases

Engineering Contradiction:
Improveair qualityVSAvoidfan energy consumption
Core Design Contradiction:
Object-affected harmful factorsVSUse of energy by moving object

Solution Approach 1:

The ventilation system dynamically adjusts its operation based on real-time conditions. The control unit activates the fan only when CO2 levels exceed a threshold and the elevator is stationary, deactivating it when the elevator is in motion or CO2 levels are acceptable. This dynamic operation maintains air quality when needed while minimizing energy consumption during normal operation.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system changes its operational parameters based on detected conditions. The control unit monitors CO2 concentration levels and elevator motion status as key parameters, adjusting the fan's on/off state accordingly. This parameter-based control ensures the ventilation system operates only when necessary, balancing air quality maintenance with energy conservation.

Inventive Principle:
Principle #35Parameter changes

3Object-affected harmful factors

If the ventilation system activates frequently, then CO2 buildup is prevented, but wear and tear on components increases

Engineering Contradiction:
ImproveCO2 buildupVSAvoidcomponent durability
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The system performs preliminary detection of CO2 levels and elevator motion status before activating the fan. The CO2 sensor continuously monitors air quality and the motion sensor detects elevator movement in advance, allowing the control unit to make informed decisions about fan activation. This preliminary action prevents unnecessary fan operation and reduces wear on components while still preventing CO2 buildup when needed.

Inventive Principle:
Principle #10Preliminary action

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 system effectively reduces CO2 buildup and maintains air quality by forcing air exchange, even in emergency situations like power failures or when the elevator is stationary, thereby enhancing occupant safety.

Implementation Method 1

A mechanical ventilation system comprising a fan... that activates only when the elevator car is stationary and CO2 levels exceed a specified value... ensuring air exchange between the car and its surroundings

Methodology Applied
Scientific EffectForced Convection: Forced Convection

Implementation Method 2

CO2 sensor detects a CO2 content above a specified value or changes at a rate of change that exceeds a fixed value

Methodology Applied
Scientific EffectGas Detection:

Data Source

PatentEP4095082A1Ventilation system for an elevator car, elevator system and method for ventilating an elevator car
Publication Date: 2022.11.30 SCHERNIKAU MATTHIAS
  • EP4095082A1 patent drawingFigure 1
  • EP4095082A1 patent drawingFigure 2~3
  • EP4095082A1 patent drawing

AI summary

Ventilation system for an elevator car comprising: • a fan suitable for installation in or on an opening or ventilation duct of an elevator car; • a CO2 sensor generating a measurement signal dependent on the CO2 content of the surrounding air; • an evaluation unit for the CO2 sensor generating a control signal based on the measurement signal, dependent on • the CO2 content of the air surrounding the CO2 sensor and/or • changes in the CO2 content of the air surrounding the CO2 sensor; • a control unit controlling the operation of the fan, wherein the control unit or the evaluation unit has a signal input for receiving a further signal, and the control unit only activates the fan for ventilation when the control signal and the further signal are in a predetermined ratio to each other.