US Patent 11427241 Drive unit

A drive unit includes a drive wheel, a prime mover, a coupling mechanism and a support frame. The coupling mechanism includes first and second coupling members. The first coupling member includes a first opposed surface. The second coupling member includes a second opposed surface opposed to the first opposed surface. The second coupling member is attached to the first coupling member in a detachable manner. The support frame is attached to the coupling mechanism. The support frame supports the drive wheel and the prime mover. The first coupling member includes a first vertical groove and a first transverse groove on the first opposed surface. The second coupling member includes a second vertical groove and a second transverse groove on the second opposed surface. The second vertical groove is opposed to the first vertical groove. The second transverse groove is opposed to the first transverse groove.