| 摘要 |
PROBLEM TO BE SOLVED: To provide a rotation angle detector in which the reduction in detection accuracy of a rotation angle of a detection object can be suppressed even when a rotation input gear and a rotation detection gear are made of resin.SOLUTION: Each of a rotation input gear 11 and a first rotation detection gear 12 to be engaged with the rotation input gear 11 is made of resin and is manufactured by injection molding which uses a form block having a plurality of gates provided at equal angular intervals in a circumferential direction, and the rotation input gear 11 and the first rotation detection gear 12 satisfy relation Z1/G1=Z2/G2 where Z1 is the number of teeth of the rotation input gear 11, G1 is the number of gates of the form block for molding the rotation input gear 11, Z2 is the number of teeth of the first rotation detection gear 12, and G2 is the number of gates of the form block for molding the first rotation detection gear 12. The rotation input gear 11 and the first rotation detection gear 12 are engaged with each other so that parts 11b facing the gates, of the rotation input gear 11 are located in center parts 12d in the circumferential direction between adjacent parts 12b facing the gates, of the first rotation detection gear 12. |
