Patent ID: 7448656

Claim:
A dual action structural latch for securing an access door to a frame, the latch comprising: a latching member secured to the frame and defining a first aperture; a primary link; a shear link; a hook member rotationally attached to the primary link for engaging the latching member when the latch is in a closed position to resist a tensile force, and for disengaging the latching member when the latch is in the open position, including an over-center mechanism where a vector between the latching member and the joint between the hook member and the primary link passes below a joint containing the second aperture when moving between the open and closed positions; a shear pin extending so as to engage within the first aperture when the latch is in the closed position to resist a shear force and to disengage the first aperture when the latch is in the open position; a cross member rotationally coupled to the frame and defining a second aperture having the shear pin extending therethrough, the primary link having a first end rotationally coupled to the cross member; and a handle rotationally attached to the primary link and coupled to the shear pin by the shear link, the shear link reacting a pivotal action of the handle to a translation motion of the shear pin for, when moved from the closed position to the open position, sequentially withdrawing the shear pin from the first aperture and disengaging the hook member from the latching member, and when moved from the open position to the closed position, sequentially engaging the hook member with the latching member and inserting the shear pin in the first aperture.