The present disclosure concerns a closure system comprising a closure hinged to a fame by a hinge device that permits transition of the closure between open and closed positions by a combined linear movement and rotational displacement.

A door lock for a pet crate includes: a crate body provided with an opening; a door body including one end rotatably connected to one side of the opening, and a locking assembly provided at the other end of the door body and connected to the crate body. As the door body is rotatably connected to the crate body, and the door body and the crate body are provided with the locking assembly, the door body can be stably fixed to the crate body through the locking assembly to prevent the pet from pulling the door lock left and right to open the door body. In addition, the locking of the door body can be completed simply by rotating the locking assembly and pulling the locking assembly to the right, making the operation simple.