| 摘要 |
1,215,101. Toothed gearing. GENERAL MOTORS CORP. 14 Feb., 1969 [16 Feb., 1968], No. 8128/69. Heading F2Q. A deformable strain type reduction gear comprises a pair of gears 30, 34 having different numbers of facial teeth 31, 35, one gear being held against rotation, rotation of a wave generator 50 causing a travelling wave type deformation of the gear 34, which is flexible, to flex parts of its gear face into mesh with the gear 30 and produce relative rotation between the gears 30, 34. In a vehicle window actuator A, Fig. 1, a disc type reversible electric motor 15 drives an output drum 90 via two deformable strain type gear reduction stages 10, 12. Each stage comprises a two arm wave generator 50, 71 carrying rollers 48, 70, a flexible gear 34, 62 held against rotation by non-circular portions (20b, 19b) of a bearing member (16) (Fig. 2, not shown), and a rotatable output gear 30, 66. The motor shaft 14 carries wave generator 50, and the gear 30 carries wave generator 71. The gear 66 is secured to the output drum 90, which forms a gear casing. In Fig. 4, a single stage reduction gear has a wave generator 130 formed by a cam disc which bears via balls 133 on a flexible gear 110 held against rotation by dowels 112 engaging between lugs 114. A second gear is formed by facial teeth 120 on the base of a cup-shaped rotatable gear casing 102 which carries an output arm 154. Dowels 152 may engage slots 151 of the casing 102 to limit rotation thereof. |
