The present invention concerns a gear drive, in particular a drive-end gear wheel rotationally coupled to a drive disc through intermediate cushioning means. The intermediate cushioning means are elastic elements that evenly transmit the rotational load from the slave bars of the drive disc to reinforcement ribs between an inner hub and an outer flange on the gear wheel. The reinforcement ribs are advantageously designed with transition curves that evenly distribute the rotational stress tangentially onto the flange of the gear wheel.
A gear arrangement for vehicle window lift drives is known from EP-B1-0 261 525 damping disc is interposed with a drive-end worm wheel in rotating slave connection with an output-end drive disc. The worm wheel has reinforcing ribs running radially between an outer ring gear flange and an inner hub. The worm wheel engages with corresponding slots, or the drive disc with axially protruding slave cams engages with corresponding slave openings of the drive disc preferably arranged centrically between the slave slots. The slave slots and the correspondingly inserted reinforcing ribs have the same cross-section, or rather the same structural shape over their entire radial length. Axially protruding distance equalizer bars are integrally premolded on the face of the damping disc. In order to be able to resist, on the one hand, the strong tangential shearing forces acting on the reinforcing ribs when the drive disc strikes against these reinforcing ribs and, on the other hand, the strong axial tractive forces acting on the ring gear flange during the manufacture of the injection molded worm wheel, the structural elements thus strained had to be designed accordingly with material strength so as not to impair operational realibility. Moreover, for sufficient radial stiffness, the specific helical gearing-compressive load also had to be taken into account when using the gear wheel as a worm wheel in a worm gear.
USPTO Backgrounds
USPTO Backgrounds