摘要:Wolfrom-transmission are well known planetary transmission with low number of gears and used for very high transmission - ratio for example : i=100 or more. With the book of Mueller “Die Umlaufgetriebe” they are a type of reduced planetary transmission containing two simple transmission one a minus-type and one a plus-type for the two transmission inside. With a common carrier for both transmission and only one sun and two inner gears it is very compact but known for bad efficiency. Firms who produces such transmission are talking about a lot of problems, but no details are published so long. The Author will show that a calculation with low-loss-gears will improve the efficiency very much and that we can produce this type without a carrier. The forces which are active at the planet should be go direct to the housing and not about bearings in a carrier. Details and a modelling of such type will be presented in the conference.