The large dia. casing-assembled worm is made by changing the present integral worm into worm casing, worm shaft, flat key, circular nut and its stop washer five parts in total. As the worm casing becomes a single part, the conditions for it entering into the row of standard parts and universal parts organizing of specialized prodn. and entering the circulating channel are created which is benefical for prodn. and maintenance and raising the economic effect of society and enterprise. The worm casing can be made with copper or wearproof material and the worm gear with steel, thus obviously the cost will be dropped off and the copper consume will be reduced. Due to that the worm wheel matched with larg dia. worm casing is processed with the present gear cutter hob it is further convenient in prodn. and maintenance and has highber practicality. |