Patent ID: 8287392

Claim:
A PTO drive shaft for connecting a driver output shaft end to an input shaft end powering a cutterbar assembly on an agricultural crop harvester comprising: an elongate PTO drive shaft for rotatably connecting a cutterbar input shaft and a gearbox output shaft, said PTO drive shaft having a rotating axis and a telescoping connector at one end for connecting to said output shaft, and a selectively removable connector for connecting to said input shaft at the opposing end; a first guard structure connected to and encircling said drive shaft for rotation therewith, said first guard structure configured to define an annular space around a first of said drive shaft connectors; a second guard structure having a generally cylindrical extension encircling and spaced apart from said first drive shaft connector, said second guard structure extending into said annular space in a labyrinth arrangement with said first guard structure; and a spacer ring configured for disposition between said second guard portion and the gearbox, said spacer ring having a thickness along said rotating axis and being separable into at least two portions such that said at least two portions may be withdrawn radially to provide clearance for axial movement of said second guard structure thereby enabling selective axial movement of said drive shaft generally equal to said thickness.