In a key-operated lock, which element serves as the primary control to set the unlocking state?

In a key-operated lock, which element serves as the primary control to set the unlocking state?

• A. Cylinder
• B. Key
• C. Bolt
• D. Gear

Answer: (B)

The essential thing that sets the unlocking state in a key-operated lock is the key. The key provides a precise pattern of cuts that align the internal pins or wafers so the cylinder can turn. When the correct key is present, the pins align at the shear line and the cylinder becomes free to rotate. That rotation is what enables the bolt to move—retracting to unlock or extending to lock. The bolt is the actual moving piece that secures or releases the latch, and the cylinder is the rotating housing that translates the key’s action into motion. Gears may be part of some designs, but they aren’t the primary control for unlocking in a basic key-operated lock—the key is.

The essential thing that sets the unlocking state in a key-operated lock is the key. The key provides a precise pattern of cuts that align the internal pins or wafers so the cylinder can turn. When the correct key is present, the pins align at the shear line and the cylinder becomes free to rotate. That rotation is what enables the bolt to move—retracting to unlock or extending to lock. The bolt is the actual moving piece that secures or releases the latch, and the cylinder is the rotating housing that translates the key’s action into motion. Gears may be part of some designs, but they aren’t the primary control for unlocking in a basic key-operated lock—the key is.