Lock Cylinder Key Flank Segmentation for Friction and Security
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing key designs for lock cylinders face challenges in balancing a large number of possible locking secrets with ease of use and reduced frictional forces during insertion, as the angle of inclination of flanks affects the force required and wear resistance.
Innovation Solution
The key design features at least three sections on one flank, with the middle section having the greatest angle of inclination to the perpendicular, allowing for adjustable angles to minimize friction and maximize wear resistance, and includes a steep angle for the section farthest from the base to reduce wear and facilitate smooth insertion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the angle of inclination of the flanks is increased to enable a large number of locking secrets, then the number of possible locking secrets increases, but the forces required when moving the key in the lock cylinder increase
Solution Approach 1:
The flanks of the locking recesses are divided into multiple sections with different angles of inclination. Each section can have a different angle, allowing the design to optimize for both security (steep angles for large increments) and ease of use (flatter angles for smaller forces) simultaneously across different portions of the same flank.
Solution Approach 2:
Different sections of the flank have different local properties (different angles of inclination) tailored to specific functional requirements. The middle section has the greatest angle for maximizing locking secrets, while other sections have optimized angles for reducing insertion forces and managing wear.
2Force
If the angle of inclination of the flanks is made flatter to reduce forces during key insertion, then the forces decrease, but the number of possible locking secrets is reduced
Solution Approach 1:
Rather than using a single uniform angle, the flank is segmented into multiple sections. This allows the design to incorporate flatter sections for easy insertion while maintaining steeper sections elsewhere to preserve the number of possible locking secrets.
Solution Approach 2:
The local angle of inclination is optimized for different functional requirements at different positions along the flank. Flatter angles are applied where ease of insertion is critical, while steeper angles are maintained where maximizing locking secrets is the priority.
3Ease of manufacture
If one flank is arranged perpendicularly to the longitudinal direction to simplify design, then manufacturing is simpler, but the force expenditure when inserting the key increases
Solution Approach 1:
Instead of using a uniform perpendicular arrangement, the design applies different angles of inclination to different sections of the flank. This maintains manufacturing feasibility while optimizing the angle distribution to reduce insertion forces through carefully selected angle variations.
Data Source
Figure 1~4
AI summary
The key (1) has a shaft (3) comprising a key back (4) and a key front (5). Closing recesses (6, 6') are arranged in the key front for supporting pin elements (7) of a closing cylinder (2). The closing recesses are laterally defined by flanks that are divided into different sections. The flanks comprise different slope angles perpendicular to a longitudinal axis of the shaft. The recesses are designed asymmetrically, where incision bases of the recesses are arranged parallel to the longitudinal axis of the shaft.