Utility knife

Claim 1

A BLADE HOLDER COMPRISING AN ELONGATED HANDLE HAVING A BLADE-RECEIVING SLOT OPENING AT ONE END THEREOF, SAID HANDLE HAVING TWO ELONGATED MEMBERS DETACHABLY SECURED AND SEPARABLE ALONG A LONGITUDINAL PLANE EXTENDING REARWARDLY OF THE SLOT OPENING, A BLADE CARRIER RECIPROCABLY MOUNTED ON ONE OF SAID ELONGATED MEMBERS FOR MOVEMENT TOWARD AND AWAY FROM SAID SLOT OPENING, SAID CARRIER HAVING A BASE EXTENDING SUBSTANTIALLY IN A PLANE PARALLEL TO SAID LONGITUDINAL PLANE, SAID CARRIER FURTHER HAVING AN INTEGRAL LONGITUDINAL FLANGE EXTENDING SUBSTANTIALLY PERPENDICULAR TO THE BASE FOR ENGAGING THE EDGE OF A BLADE TO BE MOUNTED ON THE CARRIER, SAID INTEGRAL FLANGE FURTHER PROVIDING A RESILIENT ELONGATED PORTION EXTENDING REARWARDLY TO PROVIDE A FREE END FORMING A RESILIENT CATCH MOVABLE IN SAID LONGITUDINAL PLANE, A LOCKING CAM SURFACE ON THE HANDLE FOR ENGAGING THE CATCH PROVIDED BY THE ELONGATED PORTION OF THE FLANGE , SAID CATCH BEING INHERENTLY BIASED INTO ENGAGEMENT WITH THE CAM SURFACE BY THE RESILIENCY THEREOF, SAID AN OPERATING MEMBER FIXED TO SAID ELONGATED PORTION AND ADAPTED FOR MOVING THE CATCH OUT OF ENGAGEMENT WITH THE LOCKING CAM SURFACE AND FOR MOVING THE CARRIER WITHIN THE HANDLE.