GB1171137A - Improvements in or relating to Transportable Hoist Devices - Google Patents

Abstract

1,171,137. Builders' hoists. TORNBORG & LUNDBERG A.B. 9 Nov., 1966 [10 Nov., 1965], No. 50118/66. Heading B8H. A hoist assembly comprises a mast 1 and base frame 16 which are pivoted at 17 to a further base frame 15 and which are provided with an adjustable prop device 9 for controlling raising and lowering of the mast from and to the horizontal transport position in which the hoist assembly is supported on wheels 20. The prop device 9 consists of an arm 9a, pivoted to the mast at 12, and an arm 9b, pivoted at 13 to the arm 9a and provided with a roller 14, the arms 9a, 9b normally being supported in the position shown by stops 1c, 9c. The hoist cable 3 passes from a winch drum 4 around a pulley 5 on the mast, a block 6 on the hoist cage 2, a further pulley at the top of the mast and a pulley 7 at the base of the mast and a pulley 8 on the arm 9b. In operation, an adjustable prop 18 is secured to the cage 2 such that the cage is slightly above its lowermost position when the lower end of the prop engages the ground. The hoist cable 3 is then paid out whereby the weight of the cage causes the mast to tilt about the pivot 17 until the roller 14 engages a track 15a on the base frame 15, Fig. 2b (not shown). Thereafter, further paying out of the cable 3 allows the roller 14 to roll along the track 15, the prop device 9 first turning about the pivot 12 until the arm 9a engages the mast and then the arm 9b turning about the pivot 13, the mast thereby being lowered until the wheels 20 engage the ground. In a modification, Fig. 3 (not shown), the arms 9a, 9b are replaced by a single arm pivoted to the cage side of the mast. In a further modification, Fig. 4 (not shown), the prop 18 is omitted and a further tilting device is provided on the base frame 16 to cause the initial tilting of the mast. In a further modification (not shown), movement of the prop is effected by means of a driven gear-wheel meshing with a rack.