Chipper knife grinding method and apparatus

A method for sharpening knives of a chipper, the knives remaining in a knife basket during sharpening, the knife basket being removed from the chipper and rotatably mounted in a knife basket carrier, said knife basket having an axis, said method comprising:

• locking the knife basket against rotation;
• moving a sharpening device in a direction parallel to the knife basket axis along at least one first knife for sharpening, the sharpening device and the knife basket being stationary relative to each other in a circumferential direction about the knife basket axis;
• unlocking the knife basket and the sharpening device relative to each other, rotating the sharpening device and the knife basket relative to each another, the sharpening device proceeding to a new working position for sharpening a further knife;
• continuing the cycle of unlocking the knife basket and the sharpening device relative to each other and rotating the sharpening device and knife basket relative to each another until all knives have been sharpened;
• and
• reinstalling the knife basket in the chipper.