Abstract: A locking device for use in a trocar inserted into a body cavity. The locking device include various operating components that may be easily manipulated and recognized by a surgeon during complicated surgery, and a locking portion secured in the trocar. The locking portion may include internal threads formed only on a head, a cam operated element, resilient fingers, a collet-type locking device, or a frictional detent or opening, quickly moved into a locking position against any type of instrument passing through the trocar into the body cavity. The portion of the locking device contacting the instrument must be sized and dimensioned to provide a firm grip in the locking position, without damaging or marring the instrument against which it is locked.

Abstract: A locking device for use in a trocar inserted into a body cavity. The locking device includes an enlarged head that may be easily grasped and recognized by a surgeon during complicated surgery and an elongated shaft portion secured to the enlarged head, which is conformable to a gas opening in the trocar for quick and easy insertion into the gas opening, by turning the enlarged head. The locking device has coarse self-tapping threads formed only on an upper portion of the elongated shaft, adjacent to the enlarged head to enable the locking device to be quickly turned into a locking position for any type of instrument passing through the trocar into the body cavity. The outer and of the elongated shaft contacting the instrument must be blunt and soft to prevent damaging or marring the instrument against which it is pressed.