Assisted-opening knife
From Wikipedia, the free encyclopedia
An assisted-opening knife is a type of knife which uses an internal mechanism to open the blade from a closed position when slight pressure is applied to the thumbstud or the flipper.[1]
When the knife is in the closed position, the blade is held in place by means of 1 or 2 torsion bars. As the user applies manual pressure to the thumbstud to open the knife, a mechanism such as a torsion bar moves along a track in the liner and rotates the blade into the open position.[1]
Although commonly confused with switchblade knives, there is a difference. While a switchblade can be opened usually with the push of a button, the user of an assisted-opening knife must apply some pressure to the blade at the thumb stud or flipper.
Because the blade does not open by the push of a button or force of gravity, the assisted opening mechanism is normally not considered a switchblade.[2] Once the knife has been opened about one-quarter of the way (45°), the mechanism opens the knife the rest of the way. [3]
Other names for assisted-opening knife are: A/O Knife, Torsion Assist Knife, Assisted Knife, Spring Assist Knife, Spring Assisted Knife, Quick Release, Quick Draw, Alternative Automatic, Outburst, SpeedSafe, and the Semi-Auto.
