Sliding Pin Lock Mechanism for Overhead Door
Solution Overview
Problem
Conventional overhead door locks are prone to bending and deformation in industrial environments, leading to frequent replacements and limited security, with complex mechanisms that can be easily knocked out of alignment.
Innovation Solution
A track-mounted overhead door lock mechanism featuring a round rod or dowel that slides through a hole in the track to block roller movement, utilizing a coil spring and swing arm for locking, with a microswitch that only activates when the door is closed, and a padlock for enhanced security.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a sheet steel bent into a box shape is used for the lock mechanism, then the structure is simple to manufacture, but the lock is prone to bending and deforming under force
Solution Approach 1:
The patent employs a composite construction combining heavy-duty steel components (mounting block, sliding pin, bar) with a structural frame. The mounting block is bolted to the track using substantial fasteners, and the sliding pin is a robust metal rod that resists deformation. This composite approach maintains manufacturability while significantly improving strength and resistance to bending forces compared to simple sheet steel construction.
2Reliability
If a complex mechanism with numerous moving parts is used, then the locking function is achieved, but the device is easily knocked out of alignment
Solution Approach 1:
The lock mechanism is segmented into distinct functional components: a mounting block for secure attachment to the track, a sliding pin for the locking action, a bar for engagement with the door, and a spring for automatic retraction. Each component has a specific function and is relatively simple in design, reducing the likelihood of misalignment while maintaining reliable locking functionality.
Solution Approach 2:
Instead of having the door actuate the lock mechanism, the patent inverts the approach by having the lock mechanism independently positioned on the track and passively engaged by the door's roller. The sliding pin protrudes from the mounting block and directly blocks the roller's path, eliminating complex linkages and reducing alignment issues.
3Ease of operation
If the lock mechanism is mounted on the door, then it moves with the door, but it does not provide secure anchoring to the track
Solution Approach 1:
The patent introduces the sliding pin as an intermediary element between the mounting block (anchored to the track) and the door's roller. The sliding pin protrudes from the mounting block and extends into the path of the roller, creating a mechanical interface that provides both secure anchoring to the track and functional interaction with the moving door without requiring the entire mechanism to be mounted on the door.
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 solution provides a robust, reliable, and secure locking mechanism that withstands normal use forces and shocks, increasing the lock's lifespan and security level while preventing accidental activation of dock levelers or lights.
Implementation Method 1
A coil spring is positioned over the pin or dowel between the mounting block and a retaining pin or retaining ring on the sliding pin, urging the latter towards its open or unlock position.
Data Source
AI summary
A door lock mechanism for an overhead door employs a sliding pin or rod that passes into the path of the rollers in the track, and obstructs the roller from movement in the direction to open the door. A spring in the door lock frame biases the sliding pin towards a proximal open position. The sliding pin has a swing arm that extends radially from the pin's proximal end, and which engages retaining structure at the proximal end of the door lock frame. In the lock position the distal end of the sliding pin blocks movement of wheels or rollers in the vertical track. The arm is rotated out of engagement with the retaining structure to release the pin so it may slide proximally to an unlocked position. A microswitch in the interior of the lock switches on when the sliding pin is moved to the locked position and turns off when the pin is returned to its unlocked position. A sleeve disposed over the proximal part of the spring engages the actuator of the microswitch.