| 摘要 |
PURPOSE:To keep the ratio of angular velocity constant within a prescribed angular range by continuing smoothly a pitch curve in a constant speed part having constant radius and a pitch curve in a non-constant speed part represented as an equation of ellipse in a polar coordinate with the rotational center as its pole so that a pitch circle can be formed. CONSTITUTION:In one gear 1 of a pair of gears 1 and 2, with regard to the rotational center O1, a range at an angle theta1 becomes a constant speed part 1a, and the other range becomes a non-constant speed part 1b. In the gear 2, with regard to the rotational center O2, a range at an angle theta2 becomes a constant speed part 2a, and the other range becomes a non-constant speed part 2b. In the gears 1 and 2, fellow constant speed parts or fellow non-constant speed parts are engaged respectively with fellow speed parts, and under a condition that the non-constant speed parts are engaged with each other, the ratio of angular velocity changes consecutively, and when the fellow constant speed parts are engaged with each other, the ratio of angular velocity becomes the ratio of angular velocity corresponding to the ratio of radius. Thereby, the ratio of angular velocity can be kept constant within a prescribed angular range so that the gears can be changed smoothly. |
