Dipper door latch with locking mechanism

A dipper adapted to be connected to a power shovel handle for movement therewith, said dipper having a dipper body defining a material receiving opening and a material discharging opening, said dipper body having a latch receiving opening adjacent one end of said discharging opening, said dipper further including a dipper door mounted on said dipper body adjacent an opposite end of said discharging opening for pivotal movement relative to said dipper body between a closed position and an opened position;

• a latch pivotally mounted on said dipper door for pivotal movement between a door-opened position and a door-closed position, and positioned so that when said latch is in the door-opened position, said latch is not in said latch opening, and when in said door-closed position, said latch is in said latch opening and prevents door-opening,
• a hold open mechanism for releasably holding said door latch in said latch open position when said latch is in said open position, and
• a locking mechanism for releasably locking said latch when said latch is in said door-closed position, said locking mechanism including
• one bar pivotally attached to the door, and
• another bar pivotally connected to and extending between each of the one bar and the latch.

A dipper adapted to be connected to a power shovel handle for movement therewith, said dipper having a dipper body defining a material receiving opening and a material discharging opening, said dipper body having a latch receiving opening adjacent one end of said discharging opening, said dipper further including a dipper door mounted on said dipper body adjacent an opposite end of said discharging opening for pivotal movement relative to said dipper body between a closed position and an opened position;

• a latch pivotally mounted on said dipper door for pivotal movement between a door-opened position and a door-closed position, and positioned so that when said latch is in the door-opened position, said latch is not in said latch opening, and when in said door-closed position, said latch is in said latch opening and prevents door-opening,
• a hold open mechanism for releasably holding said door latch in said latch open position when said latch is in said open position, and
• a locking mechanism for releasably locking said latch when said latch is in said door-closed position, said locking mechanism including
• a secondary latch comprising a bar holder pivotally mounted on said dipper door,
• one bar pivotally attached to the door,
• another bar pivotally connected to and extending between each of the one bar and the latch, said locking mechanism being locked by impact of one bar end into a secondary latch, said secondary latch, said bar holder having a bar holding indentation, said indentation receiving said one bar end and preventing movement of said one bar end when in a bar holding position and permitting movement of said one bar end when in a bar releasing position, and
• a false latching preventing mechanism mounted on said dipper door and extending between said dipper body and said dipper door, said false latching preventing mechanism preventing movement of said bar holder from a bar releasing position to a bar holding position when the dipper door is pivoted open, and permitting movement of said bar holder to a bar holding position when said dipper door is near a dipper door closed position.