| 摘要 |
<p>A safety device for lowering persons and loads comprises a two-piece casing, the two halves of which are symmetrical forming a cylinder therebetween,in which a piston provided with flow channels for a medium is fitted to move axially, the circumference of the piston having a sinusoidal groove in which are engaged one or several pins which are moved by a cable drum which is rotated by the cable around the outer circumference of the cylinder and in which there is a guide roll arrangement for the cable or rope, both ends of the cable hanging freely and one of them being loaded. The arrangement may further comprise three guide rolls with both ends of the cable passing over the central roll on opposite sides of it and thence between it and one of the other guide rolls on either side of it, so arranged that the loaded cable presses the central guide roll against the unloaded part of the cable which is thereby pressed against one of the guide rolls producing an additional braking effect by friction, and, furthermore, outside the casing an adjustable regulator for throttling the flow of the medium in order to adjust the rate of descent to that desired.</p> |
