抄録
A method of the geometrical design for the face gear drive has not been established. And, there is no method which determines an effective facewidth and a position of the effective portion. Therefore, it is difficult to design the face gear drive especially with offset because there are too many design parameters. In the present paper, the face gear drive with offset was discussed. In consideration of axode and hyperboloid, which were on the basis of a method for the geometrical design of the gear drive which rotate on crossed axes, a new concept "Design circle" was proposed. The position in which an effective facewidth exists was obtained approximately by the use of this concept.