Dual-Clutch Emergency Hazard Function (BS): Simultaneous Key Override
Engineering Overview: Engineering breakdown of dual-clutch emergency function Euro cylinders allowing exterior key unlocking even with an inside key left in the lock.
Technical & Engineering Specifications
| Standard | EN 1303:2015 Clause 4.8 |
|---|---|
| Operation | Operable from exterior with key left inside |
| Function Name | Dual-Clutch Emergency Function (BS / Hazard Function) |
| Clutch Material | Hardened Sintered 40Cr Alloy Steel |
The Lockout Dilemma
In standard cylinders, leaving a key turned on the inside mechanically disengages the exterior clutch, preventing outside unlocking.
Floating Dual-Clutch Kinematics
Emergency Function Cylinders (BS Function / Danger Function) incorporate a spring-loaded floating clutch sleeve:
- Simultaneous Engagement: Inserting a key from the outside compresses the central clutch spring, coupling the exterior plug to the cam even if an inside key is inserted.
- Essential Applications: Healthcare facilities, elderly residences, and family homes.
Frequently Asked Engineering & Selection Questions
Q1: What is the key installation rule for this cylinder?
Engineering breakdown of dual-clutch emergency function Euro cylinders allowing exterior key unlocking even with an inside key left in the lock.