Patent ID: 9346176
Filing Date: 2016-05-24
CPC Classification: B26B

Claim Text:
1. A method of operating a spring assisted folding knife comprising the steps of: providing a spring assisted folding knife comprising a handle, a blade, a transfer bar assembly contained in a transfer bar assembly recess, a helical spring, and a coiled torsion spring; pivotally moving said blade to overcome a blade closed bias force provided by said helical spring pressing against said transfer bar assembly followed by a blade opened bias provided by said coiled torsion spring, or to overcome a blade opened bias provided by said coiled torsion spring followed by a blade closed bias force provided by said helical spring pressing against said transfer bar assembly; and wherein said step of pivotally moving said blade comprises opening said blade from a blade closed position of said spring assisted folding knife by overcoming a closing bias force biased towards a closed blade provided by said transfer bar assembly wherein as said blade is removed from said handle, said closing bias force first increases as said helical spring is compressed by said transfer bar assembly, then said closing bias eases as a front section of said transfer assembly rotates past a sear of a blade tang of said blade and a mechanical force biasing said blade to an open position provided by said torsion spring becomes dominant, said torsion spring having been previously pre-tensioned in said blade closed position, and then reaching a blade open position.