Cart coupling assembly

A sortation conveyor system 400 comprising at least one coupling comprising a coupling disc 418 configured to engage adjacent carts, the coupling disc comprising a control slot (608, fig. 6) with one or more position registers (610, fig. 6) defined along a slot cavity to engage and lock a position register screw 421 restricting movement of the slot cavity relative to the screw in a first direction, and allow sliding movement relative to the screw in a second opposite direction in which the disc rotates, a plurality of mounting slots, a bearing slot 420 located at a centre of the coupling disc to hold a bearing and engage a bearing hub 416 of a second adjacent cart. The control slot receives the position register screw 421, each mounting slot receives a mounting pin 422, where coupling disc rotation allows translational movement altering the distance between the first and second carts. A system comprising hitch plates 410-1 410-2, a cart coupling assembly comprising coupling disc 418 engages a front hitch plate, the rear hitch plate comprising the bearing hub assembly is also disclosed. A method for adjusting length of a conveyor cart assembly comprising a coupling disc is disclosed.