Latch and lock mechanism for an aircraft cargo door assembly

A latch and lock mechanism for an aircraft fuselage door assembly wherein an outwardly opening nonplug-type closure member and an inwardly opening plug-type closure member are hinged to the aircraft fuselage along opposite sides of a fuselage doorway such that said closure members meet in the midsection of the doorway when the door assembly is closed, comprising:

• latch means affixed to fixed structure of the aircraft fuselage and positioned to receive and secure said outwardly opening closure member in a closed position, said latch means being selectively deployable between a latched position and an unlatched position by means of an elongated push-pull latch actuator rod operably coupled to said latch means;
• cam interlock means for securing said latch actuator rod with said latch means in said latched state, said cam interlock means including a lock body having first and second spaced-apart bores and a transverse channel extending therebetween, said latch actuator rod being slidably engaged in said first bore and a push-pull lock actuator rod slidably engaged in said second bore, a locking member slidably engaged in said channel, said latch and lock actuator rods having mutually opposing detents each sized to receive a portion of said locking member in locking relationship, and the dimension of said locking member along said channel being greater than the length of said channel between said bores such that said locking member is constrained to be engaged at all times with the detent of one or the other of said actuator rods;
• and
• cam-actuated linkage means responsive to opening and closing of said plug-type closure member for moving said lock actuator rod between an unlocked position wherein said detent of said lock actuator rod opens into said channel so as to receive said locking member and a locked position wherein said detent of said lock actuator rod is displaced from said channel so as to constrain said locking member to engage and lock said latch actuator rod with said latch means in said latched position, said linkage including a cam mounted on said inwardly opening closure member, said cam being cooperably engageable with a movable cam follower coupled to said lock actuator rod such that said lock actuator rod is moved to said locked position when said inwardly opening closure member is closed and said lock actuator rod is moved to said unlocked position when said inwardly opening closure member is opened.

A latch and lock mechanism for an aircraft cargo door assembly having an inwardly opening cargo door and an outwardly opening cargo ramp, wherein the cargo door and cargo ramp are hinged to the fuselage along opposite sides of a cargo doorway formed in the aircraft fuselage such that the free-swinging ends of the cargo door and cargo ramp approach one another so as to combine to form a closure member in said doorway, comprising a latch body affixed to and extending from fixed structure of the aircraft, said latch body including first and second bores passing therethrough, a lock rod slidably engaged in said first bore and a latch rod slidably enaged in said second bore, said latch body further including a transverse channel therein transecting said first and second bores, and a cylindrical interlock cam slidably engaged for reciprocal movement in said transverse channel, said latch and lock rods including opposing concave cam detents engageable with said interlock cam when said rods are positioned with their respective detents aligned with said channel, said latch rod being operatively connected to latch means for securing said cargo door to said latch body, said latch means and said latch rod being adapted such that said cam detent of said latch rod is aligned with said channel when said latch means is in a latched position, cam actuating means connected to said lock rod, said cam actuating means being responsive to said cargo door to move said lock rod to a position wherein said cam detent of said lock rod is not aligned with said interlock cam when said cargo door is in a closed position, and being further responsive to move said lock rod cam detent into alignment with said interlock cam when said cargo door is opened, the diameter of said interlock cam and the spacing between said bores of said latch body being such that said interlock cam is at all times engaged with at least one of said cam detents of said latch and lock rods.