Steam Cooker Outfeed Slicer

This slicing head cuts pet food coming off a steam cooker, with thirty 14 inch knives on a 2 inch shaft and a declumper downstream to break up anything still stuck together.

It’s the sharpening. The knives dull with use and have to come out on a regular schedule, and they come out as one shaft and blade assembly weighing about 150 lb. The plant had a gantry to lift it, but the old guard sat directly above the blades, so the gantry couldn’t reach over the assembly’s center of mass. Lifted off-center, the load would swing forward as soon as it left its bearings, bringing thirty sharp blades toward whoever was lifting it, every time the knives needed sharpening.

I designed a non-parallel four-bar linkage to replace the guard. Because the links are unequal, the guard rotates and translates at the same time, folding nearly flat behind the blades against the steam cooker. That clears the whole space above the blades, so the gantry can come straight down over the center of mass and lift the load level. The guard is clear Lexan on 304 stainless arms, so operators can see the blades, and it locks open with a detent pin alongside the customer’s safety interlock. A simple hinge could have opened the guard, but only a linkage could give the space back to the gantry.

The guard works, but it’s heavier and more awkward to lift than it should be. If you lift it from one side, it racks and binds, so it takes two people or one very careful person. The cause is in the pivots, which are bolts with nyloc nuts left slightly loose so the linkage can move. The clearance at four pivots adds up to enough slop for the assembly to go out of square. If I did it again, I would use precision pins in bushings with tighter tolerances, and the guard would open with one hand.