Over-Center Locking System for a Chaff Pan of an Agricultural Harvester

A grain cleaning system in an agricultural harvester, that includes a chaff pan with a pivotal axis near an end of the chaff pan. The chaff pan has a dual locking system coupled thereto for holding the chaff pan in two different positions. The dual locking system has a first over-center locking arrangement and a second over-center locking arrangement. The first locking arrangement is used to hold the chaff pan in an upward position when the first locking arrangement is locked. The first locking arrangement includes a first linkage element; and a second linkage element. The second locking arrangement holds the chaff pan in a locked downward position when the second locking arrangement is locked. The second locking arrangement includes a first linkage element; and a second linkage element. The first linkage element of the first locking arrangement is also the first linkage element of the second locking arrangement.