What is a freewheeling cylinder?
Freewheeling (Dutch: vrijloop) means a part can turn freely without transmitting force. In door hardware this refers to the freewheeling cylinder: a lock cylinder whose cam (the lug that operates the lock) can rotate without a key in the cylinder. The term is also used for engines: a car in neutral transmits no power to the wheels.
Why a freewheeling cylinder?
With an ordinary cylinder the cam stays fixed as long as no key is inserted. Some locks, however, need the cam to turn with the mechanism, for example:
- Panic and emergency exit locks: the lock must always open with the push bar or lever, even when the cylinder is locked and no key is inserted. A fixed cam can block the mechanism.
- Multipoint locks, both mechanical and electromechanical (motor locks), where the lock itself rotates the cam.
Tips
- Follow the lock manufacturer’s specification. It states whether a freewheeling cylinder or a cylinder with a specific cam position is required. The wrong cylinder can disable the panic function.
- Have escape doors fitted and tested by a professional. After replacement, check that the door opens from the escape side without a key.
- Mind security. Freewheeling says nothing about burglar resistance; also choose a cylinder of the required grade and suitable security furniture.
- Measure the cylinder correctly (inside and outside length from the centre of the fixing screw), so it does not protrude and cannot be snapped.
Related terms
- Panic exit device
- Multipoint lock
- Rim lock
- Lock bolt
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