Combine rock door over center closure apparatus

In a combine harvester equipped with a rock door, a rock door pivot which pivotably attaches the rock door to said harvester such that it is movable between an upper, closed position and a lower, open position, said rock door including a spring latch positioned on said rock door and a spring latch pin positioned on a latch pin arm of said rock door, said latch pin arm being pivotable between a latched position in which the pin engages said spring latch and latches said rock door in said closed position, and an unlatched position which allows said rock door to pivot to said open position, said latch pin being forced from said latched to said unlatched position by a rock striking said rock door, the improvement comprising a rock door over center closure apparatus for facilitating the closing and latching of said rock door, said apparatus comprising:

• a. a first lever arm connected to rotate about said rock door pivot;
• b. a second lever arm rigidly connected to the rock door pivot so as to rotate with the rock door;
• c. a stop member attached to said second lever arm, said stop member being positioned to engage the first lever arm as it rotates about the rock door pivot;
• d. a linkage arm connected near a first end to said first lever arm;
• and
• e. an over center assembly connected near a second end of said linkage arm, said over center assembly being movable between a free rotating position and an over center position, said over center assembly, when in said over center position, causing said first lever arm to hold said rock door in said closed position such that said rock door latch pin arm can be conveniently pivoted to said latched position.

In a combine harvester equipped with a rock door, a rock door pivot which pivotably attaches the rock door to said harvester such that it is movable between an upper, closed position and a lower, open position, said rock door including a spring latch positioned on said rock door and a spring latch pin positioned on a latch pin arm of said rock door, said latch pin arm being pivotable between a latched position in which the pin engages said spring latch and latches said rock door in said closed position, and an unlatched position which allows said rock door to pivot to said open position, said latch pin being forced from said latched to said unlatched position by a rock striking said rock door, the improvement comprising a rock door over center closure apparatus for facilitating the closing and latching of said rock door, said apparatus comprising:

• a. a first lever arm connected to rotate about said rock door pivot;
• b. a second lever arm rigidly connected to the rock door pivot so as to rotate with the rock door;
• c. a stop member attached to said second lever arm, said stop member being positioned to engage the first lever arm as it rotates about the rock door pivot;
• d. a linkage arm connected near a first end to said first lever arm;
• and
• e. an over center lever arm connected near a second end of said linkage arm, said over center lever arm being pivotable between a free rotating position and an over center position, said over center lever arm, when in said over center position, causing said rock door to be held in said closed position by the over center lever arm, the linkage arm, the first lever arm and the second lever arm such that said rock door latch pin arm can be conveniently pivoted to said latched position.