Patent ID: 6682437
Filing Date: 2004-01-27
Classification: F02B,F16C,F16F,Y10T

Abstract:
A statically unbalanced balance shaft for canceling an unbalance force of an engine, the balance shaft having an axis of rotation, comprising:a first bearing journal located adjacent a first end of the shaft, said first bearing journal having a first end side and a second bearing journal side; a second bearing journal located adjacent a second end of the shaft, said second bearing journal having a second end side and a first bearing journal side; a first counterweight positioned adjacent said second bearing journal side of said first bearing journal and being offset from the axis of rotation in one direction; a second counterweight of greater unbalance moment magnitude about a midpoint of said first bearing journal than said first counterweight, said second counterweight positioned adjacent said first end side of said first bearing journal and being offset from the axis of rotation in the same direction as said first counterweight; and a third counterweight of unbalance magnitude less than said first counterweight located adjacent said second bearing journal, said third counterweight also being offset from the axis of rotation in the same direction as said first counterweight; wherein each of said first counterweight, said second counterweight, and said third counterweight and adjacent structural elements have combined center of gravities to produce a composite Effective Plane of Static Unbalance at a location substantially within the working length of an outer diameter of said first bearing journal.