Underground Chamber Grid Hinge for Tolerance-Tolerant Installation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing secondary closure devices for underground access chambers require precise positioning and complex manufacturing, leading to high costs and installation challenges due to significant dimensional tolerances in chamber construction.
Innovation Solution
A secondary closure device with supports featuring C- or S-shaped slots and angle brackets allows for easy, tool-free installation and adjustment, accommodating manufacturing tolerances up to 20-30 mm, and includes a locking mechanism for secure closure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the grid supports are fixed or welded to the chamber walls or frame with high precision positioning, then the grid can be securely installed and function reliably, but the manufacturing cost increases and the installation becomes more difficult due to complex positioning requirements
Solution Approach 1:
The support system transitions from a fixed rigid structure to a dynamic adjustable structure. The supports can be positioned at different locations along the longitudinal axis of the chamber and adjusted to accommodate varying dimensional tolerances. This dynamic positioning capability allows the same support design to be used across different chamber sizes without requiring precise pre-positioning, thereby reducing manufacturing complexity while maintaining secure installation.
Solution Approach 2:
The support design is made universal to accommodate various chamber dimensions and tolerance ranges. The same support structure can be installed at different positions and orientations depending on the specific chamber geometry. This multi-functionality eliminates the need for custom-positioned supports for each chamber, reducing both manufacturing complexity and installation difficulty while ensuring reliable grid attachment.
2Adaptability or versatility
If the grid supports are designed with complex positioning features to accommodate dimensional tolerances, then the grid can be installed on chambers with varying dimensions, but the manufacturing cost increases
Solution Approach 1:
Instead of manufacturing supports with complex fixed positioning features, the design uses dynamically adjustable supports that can be positioned during installation. The supports include adjustment mechanisms that allow them to accommodate dimensional variations in the chamber without requiring precise manufacturing tolerances or complex geometries. This approach maintains adaptability while significantly simplifying manufacturing.
Solution Approach 2:
The support system allows for parameter changes in position and orientation during installation rather than requiring precise predetermined parameters. The supports can be moved along the chamber walls and adjusted to the optimal position, transforming the problem from one of manufacturing precision to one of installation flexibility. This reduces manufacturing costs while maintaining adaptability to dimensional variations.
3Reliability
If the grid is made secure and resistant to falling into the chamber, then safety is improved, but the device complexity and installation difficulty increase
Solution Approach 1:
The support system is segmented into modular components that can be independently installed and adjusted. Rather than a single complex integrated support structure, the system uses multiple simpler support elements that can be attached at different locations. This segmentation reduces installation difficulty while maintaining the overall security and reliability of the grid attachment through distributed support points.
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
The invention relates to a secondary closure device for an underground chamber, installed under a main closure device, in order to at least partially close access to a bottom of said underground chamber. It comprises a grid having a transverse axis, supports (6A) adapted to support the grid in a closed position comprising a first support (7A) forming a hinge with the transverse axis, so that the grid can be pivoted to an open position, and a second support (8A). The first support (7A) and the second support (8A) are positioned on opposite walls of the underground chamber.The first support (7A) comprises two wings (18) parallel to each other and perpendicular to the transverse axis, each wing (18) comprising a slot (19) of complex trajectory and having a width slightly greater than the diameter of the axis, allowing the sliding of the axis from an entrance of the slot to a terminal portion allowing the rotation of the grid around the axis. The terminal portion is straight and allows a longitudinal translation of the transverse axis.