Harvester cutterhead knife sharpening device

Abstract

A forage harvester includes a rotary cylinder-type cutterhead mounted in a housing and having a plurality of knives with cutting edges that generate a cylinder as the cutterhead rotates. A sharpening mechanism for the knives includes a pair of closed housings mounted on the opposite side walls of the cutterhead housing and a support member extending between said housings adjacent the cutterhead housing periphery, the opposite ends of the support member extending through openings in the housings and into the housing interiors. The openings are substantially larger than the support member to permit adjustment of the support member toward and away from the cutterhead periphery, and a pair of flexible seals are interposed between the ends of the support members and the respective housings to seal said openings. A manually rotatable crankshaft extends between the opposite housings and worm gearing connects the crankshaft to a threaded rod in each of the housings, each of said rods being threadable in one end of the support so that roration of the crankshaft causes adjustment of the support member toward and away from the cutterhead. A carrier is slidably mounted on the support member through a linear ball bearing and a sharpening stone is bonded to the carrier adjacent the cutterhead periphery, the carrier being reciprocatable back and forth along the support member by means of handle extending through the cutterhead housing side wall, so that the stone can be reciporcated back and forth across the width of the cutterhead as it is brought into engagement with the cutterhead knives by rotating the crankshaft. An interlock between the crankshaft and a door in the cutterhead housing prevents rotation of the crankshaft unless the housing door is closed.