GB1306035A - - Google Patents

Abstract

1306035 Ratchet hoists DUFF-NORTON CO Inc 14 Jan 1971 [14 Jan 1970] 1912/71 Heading B8B A ratchet lever operated hoist having a cable or web 40 comprises a drum 15 and a reversing ring 22 rotatable about the drum shaft 20, the ring having a central control finger 34 and two flanking fingers 35, 36, the latter being engageable with a drum holding pawl 25 and a drum operating pawl 26 during drum operation by an adjustable hand lever 14 when a lowering operation of the hoist has been selected by movement of a control lever cam 32 controlling the position of the central finger 34. A load pulley block mounted in a bight of the cable 40 between the drum and a support hook 37 located on a part 12 of the housing, is raised by anti-clockwise movement of the lever 14 whereupon the operating pawl 26 causes rotation of the drum through a ratchet wheel 18 integral therewith, the holding pawl 25 locking the wheel 18 as the lever 14 is retained for another operating stroke. During the above operation the control lever cam 32 is set as shown and the finger 34 of the reversing ring 22 is spring biased into engagement therewith. For lowering the block, the cam 32 is set into a vertical position whereupon the finger 34 moves anti-clockwise under the force of a spring 24 causing the finger 35 to lift the holding pawl 25 out of engagement with the ratchet wheel 18, With clockwise movement of the handle 14 therefor, the cable 40 is unwound until the reversing ring is turned clockwise due to engagement between the pawl 26 and finger 36 to allow re-engagement of the pawl 25 and wheel 18. With anti-clockwise movement of the lever 14, the pawl 26 is not disengaged from the finger 36 until the finger 35 re-engages the pawl 25 and spring biased rotation of the ring 22 is prevented. A free wheeling of the drum for paying out unloaded cable may be effected by disengaging the pawl 26 from the ratchet wheel 18 either directly or by depression of a quick lowering button on the handle 14, while the pawl 25 is held disengaged by the reversing ring finger 35. A rapid winding in of the unloaded cable may be effected by a crank handle on the drum. A spring steel guard 41 passing over the drum 15 guides the cable thereonto after passing through a cable guide ring 42. In the embodiment of Fig. 11 (not shown), a load carrying web is used and is looped at one end to be pinned into a slot formed in the drum hub.