Roll up pick-up truck box cover with lock down slats

1. A cover assembly for a pick-up truck box, comprising:

a roll up cover including: a plurality of slats with a first hinge element on a first side of substantially each slat pivotally attached to a second hinge element on a second side of an adjacent slat, to form a pivot joint between adjacent slats, and a flexible material covering at least the pivot joints between adjacent slats;

first and second side rails attachable to opposite sides of a vehicle box having a front end and back end;

with the roll-up cover rollable or foldable on the side rails, starting from the back end of the box, from a closed position, to an open position; and

end fittings attached to opposite ends of at least a plurality of the slats and engageable with the side rails to lock the cover onto the box, with each end fitting having a seal slot, and further comprising a resilient seal having a slot section extending through the seal slots, and with the resilient seal having an inner arm extending over the at least two slats, and an outer arm extending over a top surface of a pick up truck box rail.

2. The cover assembly of claim 1 wherein the flexible material is attached to top surfaces of the slats.

3. The cover assembly of claim 1 with the first hinge element comprising a curved lip and the second hinge element comprising curved hook.

4. The cover assembly of claim 3 with the curved lip is entirely below a top surface of the cover.

5. A cover assembly for a vehicle box, comprising:

a plurality of slats with each slat pivotally connected to at least one adjacent slat;

a flexible material on a top surface of the slats

end fittings attached to opposite ends of the slats;

first and second side rails attached to the vehicle box; and

a locking element associated with each side rail movable to engage and hold the end fittings onto the side rails, with the locking element including a hook on a roll rod pivotally positioned within an arc section of the side rail, with the roll rod movable from a first position wherein hook projects into a slot in the end fittings, to a second position wherein the hook is withdrawn from the slot.

6. The cover assembly of claim 5 with the end fittings having a flat bottom surface supported on the side rails.

7. The cover assembly of claim 5 with the roll rod and the side rail having substantially the same length and further comprising a drive plate rigidly attached to the back end of the roll rod, with the drive plate rotating the roll rod when the cover is closed over the drive plate.

8. The cover assembly of claim 5 wherein the cover rolls up or folds up starting at the back end of the box.

9. The cover assembly of claim 5 with the slats pivotally attached to each other to allow the cover to roll up only in a roll up direction wherein the top surfaces of the slats move towards each other, and with bottom surfaces of the slats facing outwardly, and not vice versa.

10. A cover assembly for a pick-up truck box, comprising:

a roll up cover including: a plurality of slats with a first hinge element on a first side of substantially each slat pivotally attached to a second hinge element on a second side of an adjacent slat, to form a pivot joint between adjacent slats, and a flexible material covering at least the pivot joints between adjacent slats;

first and second side rails attachable to opposite sides of a vehicle box having a front end and back end;

with the roll-up cover rollable or foldable on the side rails, starting from the back end of the box, from a closed position, to an open position; and

end fittings attached to opposite ends of at least a plurality of the slats and engageable with the side rails to lock the cover onto the box, with the end fittings including a slot and further including a roll rod in each of the side rails having a hook section that moves in a circular arc into contact with the end fittings, as one or more of the slats at a back end of the cover move into the unrolled position.