| 摘要 |
A corn kernel cutter of known design has a rotating head upon which cutting knives are pivoted and which mounts a shiftable ring that makes a pin and slot connection with the knives so that they open and close simultaneously. The knives are formed with counterweights which urge their cutting edges inwardly during normal operation. The corn cutter has conventional opposed sets of feed rollers which receive the ears smaller end first from a cutter feeder conveyor. A sensor switch is actuated by opening of the entry feed rollers by an ear and is connected to a control circuit including time delay relays. When the entrance of an ear is first sensed by the feed rollers, a reverse time delay relay is energized and if the corn is cut and clears the sensor feed rollers in normal fashion, the reverse time delay relay has no effect. If an ear of corn becomes jammed in the cutter long enough for the reverse time delay relay to time out, a control circuit reverses the drive to the cutter head, the feed rollers and the conveyor, which withdraws the jammed ear from the cutter. After the elapse of a short period of time, a forward time delay relay operates to again drive the machine in a forward direction and the ear is re-presented to the cutter. This forward and reverse action takes place over three cycles, after which the control circuit stops the machine, in case the ear has not passed through the cutter. Upon reversing of the drive, the direction of cutter head rotation is such that the reverse acceleration of the knife pivots and the inertia of the knife counterweights sets up a force couple that causes the knife cutting edges to automatically retract from the jammed ear during acceleration of the cutting head in the reverse direction, so that no added mechanical devices are required in the cutter head for opening the knives and clearing the jammed ear.
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