GB401307A - Improvements in hoists - Google Patents

Abstract

401,307. Winding and paying-out apparatus &c. TRIGGS, W. W., 57, Lincoln's Inn Fields, London.-(Ingersoll-Rand Co. ; 15, Exchange Place, Jersey City, New Jersey, U.S.A.) May 3, 1932, No. 12775. [Class 78 (v).] In a self-sustaining winding gear, a clamp member, movable to engage friction means with the hoisting drum, is rotatable with said drum and connected thereto by a spiral spring which maintains the clamp member in a non-operative position while the drum is moving in one direction and permits the clamp member to press the friction means into engagement with the drum when the latter moves in the reverse direction. As shown, the drum 90, driven through epicyclic gearing by a shaft 26 coupled to the shaft 16 of an electric motor, is provided with a flange 106 having a threaded portion 112 connected by a spiral spring 136 to a clamp member 124 having a threaded hub 125. When a load is being raised, the clutch facings 128 of a friction clutch 126 hold the member 124 against rotation so that it moves away from the drum against the tension of the spring 136. The spring winds up until its tension overcomes the friction of the clutch facings and permits the drum to rotate the member 124, the clutch facings being held against rotation by a hand-controlled brake band 62 engaging a flange 126a. When the driving motor is stopped and the drum starts to revolve in a reverse direction, the tension of the spring 136 is relaxed so that the clutch facings cause relative rotation between the drum and the member 124 and the latter forces the clutch facings against the flange 106.