| 摘要 |
<p>Automatically opening and closing door for a railway hopper waggon. The door (3) is carried by two pairs of rollers, an upper pair (4) and a lower pair (5), each roller moving in a curved slot (7, 8), these two slots not being parallel so that, when it opens under the effect of the weight of the material contained in the hopper (1), the door (3) is displaced simultaneously angularly, outwards and upwards, and that its centre of gravity is thus, in the open position, at a level above that which it occupies in the closed position, the door (3) being opened by the pressure of the material and closed by gravity. <IMAGE></p> |
