US Patent 12005947 Drive unit

A drive unit includes a support frame, a drive wheel and a prime mover. The support frame is disposed to be pivotable about a pivot axis. The drive wheel is supported by the support frame. The prime mover is supported by the support frame. The prime mover drives the drive wheel. The support frame and at least one member form a pivot unit. The at least one member pivots together with the support frame. The pivot unit has a center of gravity disposed on the opposite side of the pivot axis with respect to the drive wheel.