| 摘要 |
PURPOSE:To prevent the generation of backlash and a tooth hitting sound by meshing a profile shifted gear part with a mating gear with which a main gear is meshed, with an annular elastic body being deflected, in a gear device used for a motor-driven power steering device, etc. CONSTITUTION:In this gear device, a profile shifted gear part 31 which has a tooth profile shifted so as to make a tooth thickness larger than the tooth profile of a main gear 30 and which is formed with a metal material into an annular shape, an annular elastic body 32 provided in alignment on the inner peripheral part of the gear part 31, and a sub-gear 34 which is provided in alignment on the inner peripheral part of the elastic body 32 and which consists of a metallic base part 33 fixed in an integrated form to the main gear 30 side, are provided in alignment on one side part of the main gear 30. A retainer board 35, together with the metallic base part 33, is integrally fixed to the main gear 30 side with bolts 36. Also, the annular elastic body 32 made of an elastic material such as nitrile rubber, etc., together with the profile shifted gear part 31 and the metallic base part 33, is linked in an integrated form to the sub-gear 34. Accordingly, backlash at the time of meshing can be eliminated due to the existence of the profile shifted gear part 31 which is displaceably provided by means of the annular elastic body 32 on the sub-gear 34. |
