Chipper knife assembly

Abstract

The present invention is a knife assembly for a chipping canter or a mechanically similar device. In its basic form it comprises four parts: a knife holder, a knife, a knife retaining pull down block, and a tapered draw bolt to tighten the assembly. The knife holder is constructed to engage a conventional seat in a chipper head segment. It has an arcuate front surface to receive the knife element. The knife element has a rib on its rear surface which has a dovetail or T-shaped flange. The pull down block is similarly configured with a female dovetail or T-slot to grasp the rib flange on the back of the knife holder. A tapered bolt is threaded into the knife holder and passes through a similarly tapered hole in the pull down block. As the bolt is screwed into the knife holder, the pull down block and encompassed knife element are drawn to the rear where they are tightly frictionally held against the knife holder. The knife element may have an adjusting screw which seats against an appropriate portion of the knife holder for controlling the cutting height of the knife. For maintenance it is not necessary to remove the knife holder from the chipper head segment. The knife may be removed by loosening the tapered bolt and sliding it out of the knife holder. The knife element may be simply sharpened by a conventional grinding wheel which need not be configured in any special manner. Repeated tests have shown that a knife element of the present assembly will have a life cycle approximately 30% longer than conventionally used one-piece knives.

Dependencies are inferred from the claim text.