Sacrificial Shear Pins in Drive Cams: Limiting Mortise Lockcase Stress Under Vandalism
Engineering Overview: Technical analysis of sacrificial shear pins connecting cylinder plugs to drive cams, protecting internal mortise lockcase gears under forced torque.
Technical & Engineering Specifications
| Benefit | Prevents door destruction during forced vandalism |
|---|---|
| Protects | Multi-Point Lockcase Gearboxes & Internal Shootbolts |
| Mechanism | Torque-Limiting Sacrificial Cam Shear Pin |
| Calibrated Shear Torque | 18.0 N.m +/- 2.0 N.m |
Protecting High-Cost Mortise Gearboxes
Forcing heavy pipe wrenches on a key can destroy expensive internal multi-point lockcase gearboxes inside the door.
Torque-Limiting Shear Pin
- Calibrated Shear Pin: A precision brass shear pin connects the plug to the cam with a calibrated shear limit of 18 N·m.
- Controlled Failure: Excessive forced torque shears the pin, spinning the plug harmlessly without damaging the internal lockcase deadbolt.
Frequently Asked Engineering & Selection Questions
Q1: What is a sacrificial shear pin in a lock cam?
A calibrated pin that breaks safely if extreme force is applied to the key, protecting the expensive lock mechanism inside the door from damage.