| 摘要 |
<p>A tractor gearbox has a gear wheel coupling with an operating collar (14) which is normally held in a neutral position by radially spring loaded pins (16, 17, 18). The collar (14) has internal gear teeth (15) which, after coupling, are in mesh with either one of the neighbouring gear wheels (1, 2). Before the gears are coupled, a synchronising assembly produces equal rotational speed between the gear wheels. A number of friction discs (27) are located in an annular chamber formed by two tapered friction rings (26, 29). When the collar (14) is operated, the axial force moves the friction discs (27) into a true radial plane, thus producing a lever action which increases the operating force. An externally tapered friction ring (19) is then pushed into a matching groove of the selected gear.</p> |
