Eccentric Axis Escape Door Torque Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional escape doors in traffic tunnels face difficulties in opening against excess air pressure, especially during incidents like fires, due to the pressure acting on the entire door surface, and require costly wall bulges for sliding doors to reduce opening effort.
Innovation Solution
The escape door features a first axis of rotation positioned at an eccentric distance from the door leaf's longitudinal sides, utilizing the resulting torque to open the door leaf, which can be adjusted based on pressure conditions, and includes a closing weight mechanism and fire protection seals for automatic closure and gas-tight sealing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If conventional swing doors are used, then the door structure is simple, but the door is difficult to open against excess air pressure during incidents
Solution Approach 1:
The patent positions the first axis of rotation at an eccentric distance from the longitudinal sides of the door leaf, creating an asymmetric configuration. This asymmetry allows excess air pressure to generate a beneficial torque that aids door opening during incidents, resolving the contradiction between operational ease and structural simplicity.
Solution Approach 2:
The patent converts the harmful effect of excess air pressure acting on the door into a beneficial opening torque. By positioning the axis of rotation eccentrically, the pressure differential that would normally resist door opening is transformed into a force that assists opening, allowing the door to be easily opened even during incidents with high pressure differentials.
2Ease of operation
If sliding doors are used to reduce opening effort, then the door opens easily against pressure, but costly wall bulges are required for installation
Solution Approach 1:
The asymmetric positioning of the first axis of rotation from the longitudinal sides creates a torque mechanism that enables easy door opening without requiring the complex wall bulge structures needed for sliding doors. This maintains operational ease while eliminating the manufacturing and installation costs associated with sliding door infrastructure.
Solution Approach 2:
The patent replaces the mechanical sliding door system (which requires wall bulges and tracks) with a rotary door system utilizing eccentric axis rotation. This substitution achieves comparable ease of opening while avoiding the costly structural modifications required for sliding doors.
3Ease of operation
If the first axis of rotation is positioned eccentrically, then torque is generated to aid opening, but the door requires a closing mechanism to maintain sealing
Solution Approach 1:
The patent employs a closing weight connected via cable pull to the first pivot bearing, creating a counterbalancing force that automatically closes the door after opening. This counterweight mechanism maintains the gas-tight seal while requiring minimal additional complexity compared to the beneficial torque generation from eccentric axis positioning.
Solution Approach 2:
The closing weight mechanism provides automatic door closure without requiring active control systems or complex actuators. The gravitational force on the weight self-regulates the closing action, maintaining the seal through a passive, maintenance-free system that adds minimal complexity.
4Ease of operation
If the door opens in the direction of excess pressure, then opening is easier with eccentric axis, but gas-tight sealing during fires becomes more difficult
Solution Approach 1:
The closing weight mechanism ensures the door returns to and maintains its closed position, ensuring gas-tight sealing during fires. The gravitational counterbalance overcomes the pressure differential, reliably maintaining the seal even when the door opens in the direction of excess pressure during normal operation.
Solution Approach 2:
The patent employs fire protection seals comprising intumescent materials that expand under heat to maintain the gas-tight seal. These composite sealing systems ensure reliable fire resistance while allowing the door to open in the direction of excess pressure during normal operation.
Data Source
AI summary
The invention relates to an escape door (11) for separating a tube of a traffic tunnel from an escape route under positive air pressure, comprising a door leaf (13) that can close the opening between the tunnel tube and the escape route, a first pivot bearing (17) which is connected to the door leaf (13) and forms a first axis of rotation about which the door leaf (13) can be rotated between an open position and a closed position, and a door frame (15) which frames the opening and on which the first pivot bearing (17) is arranged. The first pivot bearing (17) is slidably mounted in a guide which is formed along the door frame above the opening and is connected to the upper side of the door leaf (13) at a distance from its longitudinal sides (31, 33).Two lever arms (23a, 23b) are connected to the door leaf (13) via a second pivot bearing (21a, 21b) forming a second axis of rotation and are attached to the door frame (15) via a third pivot bearing (27a, 27b) forming a third axis of rotation (25). The first, second, and third axes of rotation are aligned parallel to each other. The air pressure can act on the door leaf surface oriented towards the escape route on both sides of the first axis of rotation.