Abstract: The curve parameters are optimized within the pin gear housing in two teeth difference cycloid speed-reducer. The curve parameters within the pin gear housing serve as design variables; it is that the cycloid gear can be mounted successfully at any place and the curve is without interference that are regarded as constraints; that the strength and stiffness of the pin gear housing is weaken least serves as optimum objective. A computer program is worked out by which parameters can be optimized, installing clearance can be calculated and drafting figure can be examined. This program can be easy to use in different conditions and it has the instructive significance in making the pin gear housing.

Key words: Cycloid speed-reducer, Optimization design, Pin gear housing, Two teeth difference cycloid gear