Cylinder Lock Key Stabilizing Insert Design

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Cylinder lock keys are costly to produce and prone to damage due to material inefficiencies and susceptibility to foreign body ingress, leading to potential breakage and malfunction.

Innovation Solution

Incorporating a high-strength stabilization insert in the key shank, which reduces material thickness while enhancing strength and security, and utilizing a design with a smaller lock cylinder cross-section to prevent foreign body penetration.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the key shaft is made with sufficient material thickness to prevent breakage, then the key becomes more durable, but the material usage and production costs increase

Engineering Contradiction:
Improvekey shaft durabilityVSAvoidmaterial usage
Core Design Contradiction:
ReliabilityVSLoss of substance

Solution Approach 1:

The key shaft is constructed as a composite structure combining a base material (such as plastic or polymer) with a reinforcing insert made of higher-strength material (such as metal or fiber-reinforced polymer). The insert is positioned within a cavity in the key shaft to provide localized reinforcement without requiring the entire key shaft to be made from high-strength material, thus reducing overall material usage while maintaining durability.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

Instead of uniformly thickening the entire key shaft to prevent breakage, the reinforcement is applied locally at specific critical areas where the key shaft is most susceptible to damage. The insert is positioned in the key shaft at locations subject to highest stress during operation, providing targeted strength enhancement only where needed, thereby minimizing unnecessary material consumption in other areas.

Inventive Principle:
Principle #3Local quality

2Reliability

If the key shaft material thickness is increased to prevent breakage, then the key becomes more resistant to damage, but the production costs increase

Engineering Contradiction:
Improvekey shaft resistance to damageVSAvoidproduction cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The manufacturing process involves combining a cost-effective base material for the key shaft with a more expensive but higher-strength insert material. The base material can be produced using standard molding techniques, while the insert is separately manufactured and then integrated into the key shaft cavity. This approach allows optimization of production costs by using cheaper materials where sufficient strength is provided and reserving expensive high-strength materials only for the critical reinforcement areas.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The key shaft is divided into two functional components: a base structure made from cost-effective material that provides the overall key form and function, and a separate reinforcing insert made from higher-strength material that is inserted into a pre-formed cavity. This segmentation allows each component to be manufactured independently using optimized processes for its specific requirements, potentially reducing overall production cost compared to manufacturing the entire key shaft from high-strength material.

Inventive Principle:
Principle #1Segmentation

3Ease of operation

If a wider keyway is used in the lock cylinder, then the key can be inserted more easily, but the risk of foreign object ingress and manipulation attacks increases

Engineering Contradiction:
Improvekey insertion easeVSAvoidforeign object ingress risk
Core Design Contradiction:
Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The keyway design incorporates localized structural features such as ribs, ledges, or varying cross-sectional dimensions at specific positions within the keyway. These local variations create a precise mechanical interface that guides the key into the correct orientation and position while maintaining a compact overall keyway width that resists foreign object penetration and tool manipulation attacks.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The keyway is designed with asymmetric geometric features including non-uniform width, depth variations, and angled surfaces that correspond to the asymmetric profile of the key. This asymmetric design ensures easy insertion of the properly oriented key while creating geometric constraints that prevent foreign objects and manipulation tools from entering the cylinder, as the asymmetric keyway geometry does not provide a path for symmetric or irregular objects.

Inventive Principle:
Principle #4Asymmetry

Data Source

PatentEP3739153B1Locking cylinder key and method for its production
Publication Date: 2021.06.16 BKS
  • EP3739153B1 patent drawingFigure 1
  • EP3739153B1 patent drawingFigure 2~3
  • EP3739153B1 patent drawingFigure 4

AI summary

A cylinder lock key (10) with a key bow (12) and a key shaft (16) extending from the key bow (12) along an axial direction (14) is designed and further developed for reliable operation with simple constructional means and reduced material usage such that the key shaft (16) has a stabilizing insert (22) in its half (18) axially opposite the key bow (12), which has a higher strength than the material of the key shaft (16), and that the stabilizing insert (22) has a projection (36, 38) extending from the key shaft (16) on one or both sides and serving for locking coding. A method for manufacturing such a cylinder lock key (10) and a locking system comprising such a cylinder lock key (10) and an associated locking cylinder are described.