Deep Door Plate Prevents Crowbar Prying
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing security systems for exterior doors are vulnerable to forceful entry methods, such as using a crowbar to pry the door open, despite the use of pick-resistant locks and additional barriers, which can be overly complex and costly.
Innovation Solution
A door plate with a main body of at least 0.375 inches in depth, featuring a handle aperture and fastener apertures, is installed on the door to prevent crowbar insertion and leverage, using fasteners to secure the plate to the door, thereby preventing forceful entry.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If pick-resistant locks are used to prevent lock picking, then lock security is improved, but the door remains vulnerable to crowbar prying
Solution Approach 1:
The door plate is divided into multiple segments including a main body portion and a protruding portion that extends toward the door jamb. This segmentation allows each part to serve a specific function: the main body provides structural strength while the protruding portion specifically prevents crowbar insertion between the door and jamb.
Solution Approach 2:
The solution adds a spatial dimension by extending the door plate protruding portion toward the door jamb, creating a physical barrier in the gap space. This dimensional extension prevents crowbar insertion without affecting the lock mechanism itself, addressing the vulnerability in a different spatial plane.
2Reliability
If additional entrance barriers are provided to prevent forced entry, then security is improved, but system complexity and cost increase
Solution Approach 1:
The door plate combines multiple security functions into a single integrated component: it reinforces the door structure, prevents crowbar insertion through its protruding portion, and works cooperatively with the existing lock mechanism. This merging eliminates the need for separate barrier systems while maintaining comprehensive security.
Solution Approach 2:
The door plate serves multiple functions simultaneously: structural reinforcement, crowbar prevention through its protruding portion, and compatibility with various lock types. This multi-functionality provides comprehensive security without requiring additional specialized devices or increasing system complexity.
3Strength
If a deep door plate is used to prevent crowbar insertion, then resistance to prying is improved, but manufacturing cost may increase
Solution Approach 1:
Instead of manufacturing a single uniformly thick plate, the door plate is segmented into a main body portion with standard thickness and a protruding portion with increased thickness. This segmentation allows the expensive thicker section to be produced only where needed for crowbar prevention, while the majority of the plate maintains cost-effective standard thickness.
Solution Approach 2:
The door plate implements local quality by concentrating increased thickness in the protruding portion that contacts the door jamb, while the main body portion maintains standard thickness. This localized reinforcement provides maximum prying resistance at the critical interface without unnecessarily increasing the cost of the entire door plate.
Data Source
AI summary
A door plate has a main body with a front side, a rear side, a top side, a bottom side, a first adjacent side, and a second adjacent side. The main body includes a handle aperture and fastener apertures. The handle aperture is configured to receive a door handle of the door. The handle aperture is formed through the main body from the front side to the rear side of the main body. Each of the plurality of fasteners is formed through the main body from the front side to the rear side. The main body has a depth defined by a maximum distance between the front side and the rear side of the main body at the second adjacent side of the main body. The depth of the main body militates against a prying of the door with a crowbar where the main body is installed on the door.