Sliding Fire Door Center Rail Thermal Expansion Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Slidable fire doors face issues where the expansion of the center rail due to heat leads to increased gaps between the door body and the wall or opening frame, compromising the fire protection performance by deteriorating the center rail's ability to hold the door body in place.
Innovation Solution
A fire door configuration with an outer frame, a door body, and a center rail where the center rail is fixed to the outer frame with an engaging mechanism allowing relative movement in the width direction, preventing the center rail from bending away from the door body and maintaining the gap, even when it expands due to heat.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If the center rail is fixed rigidly to the outer frame, then the structural stability is improved, but the fire protection performance deteriorates due to gap expansion from thermal expansion
Solution Approach 1:
The patent applies the dynamics principle by making the connection between the center rail and outer frame partially movable rather than completely rigid. The engaging mechanism includes a groove in the outer frame and a protrusion on the center rail that can slide within the groove, allowing the center rail to move dynamically in response to thermal expansion while maintaining structural stability. This resolves the contradiction by enabling the structure to adapt to thermal changes without compromising overall stability.
Solution Approach 2:
The patent applies parameter changes by allowing the position of the center rail relative to the outer frame to change in response to temperature variations. The engaging mechanism permits displacement along the groove when thermal expansion occurs, changing the spatial parameter of the center rail's position. This enables the system to accommodate thermal expansion while maintaining fire protection performance.
2Reliability
If the center rail is made movable to accommodate thermal expansion, then the fire protection performance is improved, but the structural stability deteriorates
Solution Approach 1:
The engaging mechanism provides controlled movement through the groove-protrusion interface, allowing the center rail to move only in the direction needed to accommodate thermal expansion (along the groove) while restricting movement in other directions. This dynamic constraint maintains structural stability while enabling necessary displacement for fire protection.
Solution Approach 2:
The connection between the center rail and outer frame is segmented into two functional parts: the groove in the outer frame that allows movement, and the protrusion on the center rail that engages with the groove. This segmentation enables independent optimization of stability (through the engaging mechanism's constraints) and thermal accommodation (through the allowed movement path).
3Reliability
If the gap between the door body and opening frame is reduced to improve fire protection, then the fire protection performance is improved, but the thermal expansion causes gap enlargement that deteriorates performance
Solution Approach 1:
The engaging mechanism with its groove and protrusion design anticipates thermal expansion by providing a predetermined path for the center rail to move. This preliminary arrangement prevents gap enlargement by allowing the center rail to shift position before significant thermal expansion occurs, counteracting the harmful effect of gap enlargement.
Solution Approach 2:
The system transitions from a static rigid connection to a dynamic connection that can adapt to thermal changes. The center rail's ability to move within the groove constraints allows the system to maintain optimal gap dimensions despite thermal expansion, preventing the gap enlargement that would otherwise occur with a rigid connection.
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 effectively suppresses the expansion of gaps between the door body and the wall or opening frame, thereby maintaining the center rail's function and enhancing the fire protection performance of the slidable fire door.
Implementation Method 1
when a fire occurs, the door body (8) and the opening frame portion (7) may expand due to the heat of the fire, and a gap may be generated. For example, when a center rail (a second vertical frame (15)) of the opening frame portion (7) expands due to heat
Data Source
AI summary
A fire door includes: an outer frame; a door body; and a center rail, the center rail is provided so as to overlap a target area in a wall orthogonal direction view, and so as to extend in a width direction between a first frame portion and a second frame portion on the side opposite to the wall body with respect to the target area, the center rail and the first frame portion are fixed to each other, the center rail and the second frame portion are engaged with each other with an engaging mechanism interposed therebetween, and the engaging mechanism is configured to allow relative movement of the center rail relative to the second frame portion in the width direction, and to regulate the relative movement thereof in the wall orthogonal direction and a slide direction.