| 摘要 |
PURPOSE:To secure a large wiping area with a sample structure, by installing a pair of pinions in a fixed sun gear provided with at least three partial gears via a planetary gear, and making a wiper arm free of slide motion with a rack part being engaged with these pinions. CONSTITUTION:A gear chamber case 7, installing a wiper arm 17 around a center pivot shaft 1 of a fixed sun gear 10 provided with at least three partial gears 10a-10c, is supported free of rotation. Inside this gear case 7, there are provided with each pair of pinions 20a and 20b rotating via planetary gears 12a, 12b and intermediate gears 21a and 21b to be engaged with these partial gears 10a-10c. These pinions 20a and 20b are engaged with a rack tooth 17a of the wiper arm 17, making this arm 17 free of slide motion. According to this method, rotation and expansion of the wiper arm 17 can be done with a simple structure without using any crank and link mechanisms and, what is more, an extensive wipering area is securable with one wiper arm alone. |
