US Patent 9260909 Cover unit including a lock mechanism

A cover unit includes a cover element for a chamber of a chassis, rotatably supported at one end of the opening and a lock mechanism to lock the cover element in the chassis. The lock mechanism includes a lock element movable in parallel between a lock position and a release position, and having a latch portion to protrude from the cover element at the lock position, an elastic element to press the lock element to the lock position, a hole to receive the latch portion protruding from the cover element and restrict a movement of the latch portion, a receive element to hold the lock element in the release position against the elastic element, and a protrusion to press the receive element when the cover element is pressed onto the opening. The receive element releases the lock element from the release position, when pressed in the orthogonal direction.