Patent ID: 6675563
Filing Date: 2004-01-13
Classification: A01D

Abstract:
A disc cutterbar comprising:a support member with a cutterhead affixed thereto, said cutterhead having a lower end adjacent the ground when in operation and an opposing upper end; a power transfer mechanism supported by said support member and including a vertical drive shaft within said cutterhead and adapted to transfer power from a power source into rotational movement in a first direction of said vertical drive shaft, said vertical drive shaft having an upwardly extending distal end; a lower hub affixed to the distal end of said vertical drive shaft and adapted to be rotated in a generally horizontal plane; a retaining bolt affixed axially to said vertical drive shaft and extending axially and upwardly away therefrom, said retaining bolt having a threaded portion adjacent the distal end of said vertical drive shaft and an unthreaded portion upwardly therefrom; an upper hub having a central bore therethrough, said bore being threaded to engage the threaded portion of said retaining bolt, said upper hub including a disc member carrying at least one knife to sever standing crop material, said threaded portion of said retaining bolt and said threaded bore being engaged such that rotation of said upper hub in said first direction forces said upper hub into more intimate contact with said lower hub; a shear mechanism operable between said upper and lower hubs such that torque is transferred from said drive shaft through said lower hub and shear mechanism to said upper hub and said disc member, whereby when said knife encounters sufficient force to cause said shear mechanism to fail, said second hub moves in a second direction relative to said retaining bolt, opposite said first direction, causing said second hub to move upwardly along the axis of said retaining bolt away from said first hub.