GB561238A - Improvements in or relating to automatic braking devices - Google Patents

Abstract

561,238. Stopping and starting mechanism. A.C.E. MACHINERY, Ltd., and EVANS, P. N. June 2, 1942, No. 7474. [Class 80 (ii)] [Also in Group XXXIV] Movement of a hand lever in either direction from a central position actuates a spring- pressed lever carrying a brake shoe to disengage the shoe from a drum and simultaneously displaces the drum to engage it with one or other of a. pair of oppositely rotating friction driving pinions by which it is driven in the corresponding direction. As shown, the drum 1 which is coupled to a gear member by which it transmits the drive to the apparatus under control rotates upon a shaft 3 mounted in eccentric bearings 2 in fixed frame members 10, 11 and the shaft with the bearing members 2 can be turned by a hand lever 6 so as to displace the drum to a small extent and thus to engage the interior surface thereof with either of a pair of oppositely rotating driving pinions as described in Specification 561,235. Rigid with the lever 6 is. a double arm 29 connected by rods 27 to one end of a lever 14, 15 pivoted at 16 to the base 17 and carrying a brake shoe 13. The shoe is pivoted at 18 to the lever so that it may be accommodated to the drum surface and a spring 19 is disposed between it and a lug on the lever arm 15. The shoe is applied to the drum by a spring 21 which bears on a fixed plate 22 and through a plate 25 on a rod 23 seated at 24 on the lever arm 15. The rod 23 slides through the plate 22. The brake shoe 13 is thus applied to the drum when the lever 6 is in the central position shown and is released when the lever is moved to either side to engage the drum with the one or the other of the driving pinions. The invention may be applied to power-driven cranes and other hoisting and lifting gear such as described in Specifications 561,233 and 561,239, [both in Group XXX].