GB191501796A - Improvements in or relating to Lift Brakes. - Google Patents

Abstract

1796. Krupp, Akt. Ges., F. Feb. 4, 1914, [Convention date]. Self-sustaining gear.-Consists in an automatic lift brake which is effective for load turning-movements in both directions on the winding-drum. The drum A, Fig. 1, has two oppositely-coiled load ropes E, E', and its shaft bears at the outer end in a fixed casing C<1> having an annular braking-surface for a band brake c<3>. This, as shown in Fig. 2, is split, and its ends are joined to its central portion by two diametral links G. Keyed to the shaft D is a disk D' having pins d<2>, which enter between the links G, and keyed to a gear-wheel J, but loose on the shaft D, is another disk H, Fig. 1, having pins h<1>, which can engage the outer surfaces of the links. The disks D<1>, H with the pins and links thus form a coupling, through which the drive is transmitted from the crank k<2> to the drum A. With a load on the rope E', say, the drum and disk D' tend to turn in the direction of the arrow x, and the pins d<2> force the links apart so as to apply the brake and hold the load. For lifting, the crank is turned in the direction of the arrow y until the pins h<1> bear against the links, as shown at I, and remove the brake, leaving the drum free for hoisting. For lowering, the crank rotation is reversed, and the pins h<1> bear on the links as shown at II, thereby removing the brake. Further rotation of the crank and disk H carries the brake band around in the direction x, and the lowering starts. If the speed of the disk D<1> and drum, due to the load, exceeds that of the disk H, derived from the crank, the pins h<1> leave the position II, and the pins d<2> apply the brake and retard the drum until the pins h<1> again free it. The brake is thus intermittently applied, and the load descends practically as though the disks D', H were permanently coupled.