{TAIL ~ The outer gear} constitutes a rigid gear 1 which is assumed to be fixed, while the inner gear constitutes a flexible gear 2 which is formed as {HEAD ~ a thin flexible ring} so as to be flexible in its radial direction 
{ TAIL ~ The outer gear } constitutes a rigid gear 1 which is assumed to be fixed , while the inner gear constitutes a flexible gear 2 which is formed as { HEAD ~ a thin flexible ring } so as to be flexible in its radial direction
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH