Door Latchbolt Segmented Engagement Angle for Security

Solution Overview

Problem

Existing door lock assemblies with latchbolts often lack enhanced security features, particularly in exit doors of large facilities, where the engagement angle between the latchbolt and strike can compromise security if the force applied exceeds a certain threshold, potentially allowing unauthorized access.

Innovation Solution

A door assembly design featuring a latchbolt with a first and second member, where the second member rotates from a fully extended position to a retracted position upon increased force, changing the engagement angle from approximately 60 degrees to 90 degrees, enhancing security by preventing door frame separation and ensuring secure locking.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the latchbolt uses a conventional single-member design with fixed engagement angle, then the structure is simple, but the security is compromised when force exceeds a certain threshold

Engineering Contradiction:

ImprovesecurityVSAvoidlatchbolt structure

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The latchbolt is divided into a first member and a second member that can rotate relative to each other. The first member engages with the strike at a first engagement angle, while the second member can rotate to engage at a second engagement angle, providing segmented security responses based on applied force

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The latchbolt transitions from a static engagement angle to a dynamic system where the second member can rotate between a first position (first engagement angle) and a second position (second engagement angle). This dynamic adjustment allows the latchbolt to adapt its security characteristics based on the force applied to the door

Inventive Principle:

Principle #15Dynamics

2Reliability

If the latchbolt maintains a fixed engagement angle, then the mechanism is simple, but unauthorized access can occur when force exceeds the threshold

Engineering Contradiction:

ImprovesecurityVSAvoidlatchbolt mechanism

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The latchbolt is divided into a first member and a second member that can rotate relative to each other. The first member engages with the strike at a first engagement angle, while the second member can rotate to engage at a second engagement angle, providing segmented security responses based on applied force

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The latchbolt transitions from a static engagement angle to a dynamic system where the second member can rotate between a first position (first engagement angle) and a second position (second engagement angle). This dynamic adjustment allows the latchbolt to adapt its security characteristics based on the force applied to the door

Inventive Principle:

Principle #15Dynamics

Data Source

PatentEP2013431B1Door assembly

Publication Date: 2016.01.13 VON DUPRIN INC

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AI summary

A latchbolt configured for use with a door lock assembly. The door lock assembly is configured for interaction with a strike coupled to a door frame, and operable to place the latchbolt in a locked configuration using the strike to generally prevent rotation of the door and an unlocked configuration to allow rotation of the door. The latchbolt includes a first member and a second member movably coupled to the first member. When the latchbolt is in the locked configuration the second member is movable relative to the first member from a first position to a second position in response to a predetermined force applied to the door.