Deere Stone Stopper

At a recent trade show, the John Deere people put out a product reveal. John Deere spokespersonTim Meister talked about the Model 8800 self propelled forage harvester with a 770+ corn head on it. A question came up about picking up rocks. “In corn applications, you don’t see a lot of stones but I have seen some people put stones in with a corn head. Typically they are chopping too low because they are chopping dirt but it’s a very common issue with grass pickups to bring stones in so what we have done is put an accelerometer on the upper front feed roll and that accelerometer estimates when the feed roll moves rather quickly as in, when a rock might go in underneath it, that roll will jump very violently and the sensor can detect that. What we have done and no one else has ever done is we put a knock sensor in the lower feed roll and it works in conjunction with our metal detector. If either of those three sensors detect metal or stones or rocks they will stop the feed rolls in less than 80 ms.